I want to start by telling everyone who has been waiting to read this thank you for your patience. I want to tell those people who weren’t very patient tough luck. I know it has taken way too long to get it out. The great majority of the time it took was in waiting for people to get uppers to me. I want to thank everyone who sent uppers for me to take a look at and shoot. All of them have been without them for months and have been very patient and generous with their property. Those few companies who sent uppers in a timely manner are owed the biggest apology. They have been without their uppers for MANY months.

As you read this, please consider the source. I am not an “end user”. I am not, nor have I ever been in the military, law enforcement or any other career/position where I would have to use a firearm to protect myself or anyone/thing else.

Briefly, my background is fine dining! After being a server in mid high to high end restaurants for  about 15 years, but being a big AR fan, I was somewhat recruited to help work in a local gun shop/range. As running the shop and making cool guns took precedence over serving fine food and wine, I had a career change. So again, please consider the source of this report as you read on. Having said that, I will tell you that I try hard to be critically observant yet pretty fair and open minded about guns and gear. I’m not a professional anything. My opinions come from my own experiences and what I have witnessed with the many different guns and gear I see at work every day, the different type of shooting I’ve done and classes I have taken over the last 10 years.

Lastly, some of my opinions may sound as if they’re coming from someone other than a casual sport/fun shooter. This is primarily because even though the majority of shooting I do is for sport and fun, when it comes down to it, the reason I own firearms at all is because I believe we all live in a world where the average Joe or Jane, may, in their lifetime, have a need to possess or use guns like the ones we are discussing. I don’t own a tinfoil hat. I am not in a militia. Sadly, I am not even prepared for the end of the world as we know it (I could probably make it through an extended zombie attack though).

Clearly my personal collection of guns, AR15 style rifles specifically, leaves the realm of practicality. There’s no doubt I’ve become a “collector” of sorts. While that is undeniable, I am not blind or ignorant to the world in which we all live. I view guns as tools and weapons first and foremost. Whatever they actually become to me, or someone else after the fact is inconsequential. The uppers I’ve had the opportunity to shoot over the last several months have all been viewed from this perspective.

This was not a scientific test. I’m a pretty regular guy without access to the types of equipment resources or support to do a truly scientific test of these uppers. That may mean that some of you don’t get the results or info you are looking for out of this test. What I have done is take a good cross section of 6.8 uppers that are readily available to the general public, and shoot them in ways the general public would. With the possible exception of the full auto portion, nothing I did couldn’t be done by anyone else on the board. However unscientific or incomplete the testing me be, I think the average shooter looking for average information on the 6.8 round and the magazines that feed them into the uppers that shoot them will get use of what we’ve done.

For a while, board members were betting on who they thought was going to “win” or do the best. As the below results will testify, there was no single upper that, in any substantial way, unilaterally broke away from the pack. Likewise, no one fell dramatically behind. Results, in large part, were surprisingly unsurprising. The ever-present human error was most likely the largest prohibitive factor in most everything done. I’ll make no excuses and wont pretend the accuracy results I came up with are the best these uppers are capable of. Many of you who shoot better, have the time to test different ammo which may shoot better, have the opportunity to shoot under better conditions can very likely get any one of the uppers to shoot better than I was able. In fact, I think the similarities in many of the groups the uppers turned in illustrate we may have been shooting to mine and the ammo‘s potential, given the conditions we were shooting in. I find it likely that the uppers themselves may be capable of different results if given the opportunity.

Though I had requested a parts sheet from (almost) everyone, many did not send a parts breakdown. If a company did not provide one, or otherwise list what was put into their upper in the previous thread, I have tried to break it down to the best of my ability.
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Uppers we received:
(for the rest of the report I am going to be listing uppers in the order they were received)

MSTN

MSTN was the first company to send us an upper. We received it on 4/3/07. Not that it mattered, but they were the only company to have an upper to me in time for the deadline. While making that deadline didn’t really wind up making a difference in who got to participate in the test, I think the fact they were on time it is important to recognize.

The package included their complete upper, a steel 15 round PRI magazine, a bore guide and custom length, single piece, coated cleaning rod with brush and jag. A small tube of “gun butter” lube, barrel break in instructions and a copy of test targets from the upper were also included. Also worthy of mention, theirs was the only upper to come with a requested breakdown of parts used and end price a consumer can expect to pay for what I received. Upper arrived broken in and ready to shoot.

The rear lug on Vltor VIS uppers have at times been unusually tight in some lower receivers. I have not yet come across one that would not fit, but I have had to use the rubber mallet to close the upper on a couple receivers. In my experience, Vltor MURs and VIS uppers have also come with dust covers that can be tight to close. MSTN’s upper was no exception. The dust cover was a little tight and the rear lug was tight in a couple lowers, in the case of the Bushmaster lower we used in the full auto testing, it fit very, very tight.

Clearly using high end parts and pieces, it was immaculate. Their choice of the Vltor VIS provides a continuous top rail for easy mounting of any and all sights and optics you could need. The VIS also allows the owner to remove the bottom rail for barrel maintenance. While this is not a critical feature, I find it an advantage over rails that do not allow this. Easily being able to get some oil on the barrel is a nice option to have.

The bolt carrier was staked well. The bolt uses an extra power extractor spring, and came with the black insert.


The M4 style feed ramps transition from upper to barrel were perfectly aligned and about as smooth and clean as I have ever seen.


The gas block contained two set screws which appear to have been counter sunk into pre-drilled divots in the barrel.


Upper/hand guard: MSTN marked Vltor 12” VIS
Barrel: Douglass 16” SS Premium Match ion bonded black.1:11 twist chambered with 2nd gen A.M.U. reamer.
Gas block: Vltor double set screw block
Gas system: Mid length, direct impingement
Muzzle device MSTN QC
Bolt group: Young Mfg hard chrome carrier with numbered bolt. Extra power extractor with black insert
Charging handle: Gas Buster
Sights: none
Panels: 3 Magpul ladders
Price for package: $1773 delivered
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KO-TONICS KT68-M4R6

Ko-Tonics had the next upper in on 5/2/07. They call it the KT68-M4R6, Combat Edition. Their upper did not come with the requested parts list and price sheet I requested, however, they conveniently posted all of that information in the thread, so that is not to be held against them.

Upper was in excellent condition and everything on the upper was put together well, however, the finish and machining of Yankee Hills FF rail and flip up front sight/gas block is not on par with what we received from the other entries which used FF rails and flip front sights. However, please take note of the price difference between this upper and the others I am comparing it to. I believe this upper was built with a balance of performance and price in mind.

The bolt carrier was staked, but not properly as I am used to seeing them. These stakes are common on most every Stag/CMT bolt carrier I have seen. The bolt used a standard extractor spring and insert.


The upper and barrel contained M4 feed ramps, but they were very shallow compared to some of the other entries.


The gas block used 4 clamping screws to secure it to the barrel.


Upper/hand guard: Stag upper, Yankee Hill mid-length
Barrel: KT68 16" barrel: 4140 chrome-lined chamber and bore, improved SAAMI-spec chamber, 4-groove 1:11" twist rifling, M4 feed ramps on barrel extension, mid-length gas system, second gas block section at rifle length, 0.84" under forend, 0.74" between gas block sections, 0.72" out to muzzle, 5/8" x 24 tpi muzzle thread, Cerakote Graphite Black finish
Gas block: YHM (see below) quad clamped
Gas system: Mid length, direct impingement
Muzzle device: A2 style
Bolt group: Stag Arms
Charging handle: Standard
Sights: YHM 9395 front, no rear
Panels: 2 Magpul ladders, 1 KAC clone pannel
Price for Package: $742
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GLOBAL TACTICAL

Global Tactical (Denny’s) was the next upper to arrive on or around 5/7/07. Upper was sent alone, but they also provided a parts list on the thread. Hawkeye came in to my job to see the upper shortly after it arrived. He informed me Denny had mentioned to him that he had briefly test fired the upper for function. Denny mentioned this himself in the initial thread. As I recall, Hawkeye also relayed to me that Denny hoped there would be some break in before accuracy shooting. This was the first but not the last time I had this request.

Using a LaRue Stealth upper and 11.0 free float rail, overall fit and finish was outstanding. I should note that it came with new foliage Magpul ladder bars, and it was the first time I had seen them available. Nice touch!

The bolt carrier was staked well and the bolt used an extra power extractor spring with black insert and O-ring.


The M4 feed ramps from the upper to the barrel were smooth, but slightly misaligned.


The gas block used two set screws, I was unable to tell of the screws were set into the barrel or not. (I could not access the gas block to take a picture)

Upper/hand guard: LaRue Stealth with LaRue 11.0 rail
Barrel: 417R G70 stainless WOA barrel, 1:11 made to Denny’s specs with WOA's 6.8 chamber
Gas block: LaRue double set screw block
Gas system: Mid length, direct impingement
Muzzle device: Smith Enterprise Vortex
Bolt group: Young NM bolt Carrier, Denny’s staked key, CMT/Stag 6.8 bolt with CS spring, black bumper and Crane O-Ring
Charging handle: CMT/Stag charging handle with Badger Ordnance Gen 1 Tac-Latch
Sights: None
Panels: 3 Magpul ladder bars
Price for Package: $1339 shipped
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JTAC

JTAC’s upper arrived next on 5/9/07. Another upper using excellent parts and pieces. This upper came alone with no parts sheet.
It was in excellent condition, fit and finish of all parts was 100%. The bead blasting on the barrel was dull and even. It was very attractive. Using the Vltor MUR, the rear lug was very tight in a couple of the lowers we used in the testing. I am not mentioning this here (or in the MSTN description of the VIS) as an advantage or disadvantage. I can see how some users could find it as either. But I do think the fact should be included.

The bolt carrier was staked, but the stake job appeared non standard. It looks like they may have used a carrier that was initially improperly staked, and then re-staked. I’d have liked to have seen a better carrier key. The bolt used a standard extractor spring and blue insert.


The feed ramps were smooth and deep, but misaligned.


The gas block used two large clamping screws.


Upper/hand guard: Vltor MUR with f/a, Daniel Defense 9” M4 rail
Barrel: White Oak 16" 6.8 SPC stainless match barrel, fine bead blasted
Gas block: PRI double clamped front sight gas block
Gas system: Mid length, direct impingement
Muzzle device: Smith Enterprise Vortex
Bolt group: CMT
Charging handle: PRI Gas Buster
Sights: PRI flip front gas block (no rear)
Panels: 3 Magpul ladders
Price for Package: $1400
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BARRETT M468

Barrett’s M468 upper followed on 5/15/07. While they were certainly not the first manufacturer to send an upper, I think it is important to note that Barrett did not have nearly the notice that many of the others did. They were also not a part of this forum that I can tell and did not know all this was happening, yet were very easy to work with and get a test upper. As one of the very first, if not the very first big name manufacturer to offer 6.8 uppers and complete guns to the commercial market, I was especially glad they decided to participate and send an upper. Their upper came with an Uncle Mikes soft side rifle case embroidered with Barrett’s logo. It came with one of their own steel 30 round magazines (the only 30 round 6.8 mag I am aware of) and 4 boxes (30 rounds per box) of Barrett’s own 6.8 ammo. Fit and finish of all parts and pieces was excellent.

The ARMS #58 SIR rail used also allows for easy removal of the bottom rail for barrel maintenance. The rail raises the optics mounting platform about a half an inch. This may cause some optics to be mounted slightly higher than you are used to, but is easily compensated for with ring/mount selection with most optics. While it is not a continuous rail, it does extend the mounting platform, and a separate section of rail is available to create a continuous rail from sight to sight. Their upper did not come with a parts list, although I did request one in my emails with them.

The gas key was staked properly.


The bolt was chromed and had the dual extractor springs.


The M4 feed ramps were smooth and nearly perfectly aligned.


The gas block was pinned, but used roll pins instead of straight or taper pins. The gas block was also threaded for the use of their suppressor (which I have yet to see or use).


Upper/hand guard: Barrett marked upper with ARMS #58 rail
Barrel: 16” 4150 steel, chrome lined 1:10 twist
Gas block: Barrett’s double pined (with roll pins) proprietary gas block/sight
Gas system: Mid length, direct impingement
Muzzle device: Barrett muzzle brake
Bolt group: Barrett, bolt has dual extractor springs
Charging handle: standard
Sights: ARMS #40L rear sight, Barrett proprietary flip up front sight
Panels: none
Price for Package: $1590 (w/o ammo)
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PRECISION REFLEX INC.

PRI’s upper arrived on 5/23/07. Dave Dunlap mentioned to me he was sending an upper he had used on a hunting trip, so it would not be new. I told him I would be commenting on the fit and finish of the uppers received, but that I would be sure to mention theirs was a used upper. While the upper was visibly used, it appeared to have been together well. The PRI top rail which connects the upper to the PRI tube provides for a continuous top rail, but raises your mounting platform by approximately a half inch. This is easily compensated for by mount/ring selection with most, but not all optic. The upper came with a steel PRI 15 round magazine and 1 box of Silver State ammo (20 rounds per box). The barrel was stainless coated black, but the MSTN QC comp was blasted stainless. I thought this took away from the upper a little visually, but understand a consumer could easily order their own upper in whatever configuration they like and my dislike for it is personal taste.

The carrier was poorly staked and the firing pin was not shrouded.



The bolt came with a standard power extractor spring and blue insert. The exterior of the extractor was marked SGC? Anyone know what that means?


The upper and barrel had good M4 feed ramps that had nearly perfect alignment.


The gas block used two large clamp screws


Upper/hand guard: Colt upper with PRI 9” Gen III forend coated black. Also came with PRI’s forearm rail connecting the upper to the rail.
Barrel: 16” stainless (I was unable to get more info on this barrel)
Gas block: PRI double clamped flip up front sight
Gas system: Mid length, direct impingement
Muzzle device: MSTN QC
Bolt group: “D” marked carrier (DPMS?) unknown bolt
Charging handle: PRI Gas Buster
Sights: PRI flip up front sight gas block, PRI flip up rear
Panels: none
Price for Package: $1500 (?)
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LWRC DMR

LWRC’s upper arrived on 5/24/07. Great looking upper. Upper arrived with two C-Products 25 round magazine and small cleaning kit. Also included was an instruction manual and Harris bipod on a LaRue QD mount that I did not use. This upper is apparently a custom build of sorts. I am sure you could order one like this from them if you chose to, but it is not a cataloged item. Fit and finish of parts was excellent. The top rail is easily removable for easy access to both the piston and barrel maintenance. The sights on the gun were somewhat unique (only in that you do not often see them) and I appreciate that sort of thing. As mentioned, the top rail of this upper is removable. While I like the ability to get to the barrel, I worry that if you attach a flip up iron sights to this portion of the rail you may have zeroing issues when you reinstall the rail. Our specific upper came with a barrel mounted front sight, so this was a non issue, but I wonder if anyone with one of these can say if it is an issue or not?

The gas key was not staked, but as a piston upper, it wouldn’t have to be. The gas key, however, was fit into a dovetail on the carrier. I thought this was pretty good thinking! The extractor came with a standard power spring and blue insert.


The M4 feed ramps were smooth and almost perfectly aligned.


The gas block was double pinned.


Upper/hand guard: LWRC Proprietary upper and mid-length railed hand guard (Gun-Kote over Type III Hardcoat anodizing)
Barrel: 14.5” stainless Lother Walther barrel coated black. 1:10 twist, Transitional chamber close to SSA. (All subsequent LWRC barrels use current SSA chambers)
Gas block: Low profile, double pinned gas block
Gas system: LWRC Short Stroke Piston System
Muzzle device: Pinned Phantom
Bolt group: LWRC Nickel-Teflon Carrier, CMT bolt
Charging handle: standard
Sights: GG&G triple clamped flip up front sight gas block (used only as front sight, not as a gas block) Matech rear
Panels: 3 Magpul ladders
Price for Package: $1800 (?)
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LMT MRP

LMT’s CQB MRP arrived on or about 5/26/07. Another company who had less time to send an upper in for testing, but got one to us in relatively short notice. Upper arrived with a torque wrench and bit factory set to the specific weight LMT requires the barrel bolts be tightened. Also included was a steel 20 round PRI magazine, instruction manual, QC checklist and Hornady 6.8 ammo sheet.. All the MRP’s I have seen, to include this one, have very clean machining and great finish. Their one piece upper and rail gives a true continuous rail. While no portion of the rail is removable for barrel maintenance, the barrel is pretty easily removed by the user, enabling them to clean and care for the exterior of the barrel. Removing and installing the barrel results in very little zero shift in my (admittedly limited) experience. I liked how their bolt carrier was stamped 6.8 in white at a spot that is easily visible through an open ejection port.

The carrier was staked very well and their bolt was chromed with dual extractor springs.



Feed ramps were smooth and close to perfectly aligned.


Gas block was secured by a single pin at the top of the barrel.


Upper/hand guard: 1 piece LMT MRP proprietary upper with continuous rail
Barrel: 16” 4150 chrome lined.
Gas block: single pinned, low profile
Gas system: carbine length, direct impingement
Muzzle device: A2
Bolt group: LMT standard f/a carrier, LMT enhanced (hard chrome) 6.8 bolt with dual extractor springs
Charging handle: standard
Sights: none
Panels: 3 LMT marked Tango Down
Price for Package:???
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AR15BARRELS.COM

AR15barrels.com upper arrived on 5/28/07. Upper came with a huge strand of stainless steel scrap from a profiling pass. Pretty interesting souvenir from a custom barrel. No parts sheet or price list, but Randall did provide an online breakdown in the previous thread. The upper arrived with the LaRue rail improperly installed. The hand guard nut was loose. Several board members and staff were there to see it. I don’t recall which Staff member was in the shop the day the upper arrived, but it was either Hawkeye or SGB. Chromeluv, 1-AR-Newbie, JohnnyEgo, JaxBushmaster, ram12375, M4Tuna and other members each saw it as well. This was easily fixed because I have the proper tools to do so, but this might have been a drag for a customer who did not have such easy access to the tools needed (a vice, a upper block and a strap wrench). Aside from this, the upper used premium quality parts with excellent fit and finish. Their stainless barrel was lightly bead blasted, so it was kind of bright for my taste, but I again recognize bead/sand blasting a barrel as something AR15barrels.com could easily do and is a matter of customer preference.

The carrier was properly staked and came with the old style firing pin retaining pin. This is the first time I had actually seen one of these. I don’t know much about them in practice, but it looks like a good strong design. The bolt used a extra power extractor spring and black insert.



The feed ramps were smooth and perfectly aligned, but were not nearly as deep as most of the other entries.


The gas block used set screws, I could not tell if they were set into the barrel. (I could not access the gas block to take a photo)

Upper/hand guard: CMT M4 receiver selected for barrel extension fit and trued, LaRue 13.2
Barrel: Stainless 17" SPR weight Krieger barrel with mid-length gas and an optional rifle gas block seat to allow for a flip-up sight forward of a 12.0 rail system
Gas block and length: MI low profile gas block
Gas system: Mid length, direct impingement
Muzzle device: Smith Enterprise Vortex
Bolt group: Young N/M M16 bolt carrier, CMT bolt
Charging handle: PRI gas buster
Sights: none
Panels: 3 Tango Down
Price for Package: $1375 shipped
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NOVESKE RIFLEWORKS

Noveske’s upper was the next to last upper to arrive on 6/4/07. Like Barrett, Noveske had among the least amount of time to prepare and send an upper. He was not involved in the thread that started this test, so was unaware of the few particulars I was asking (like parts list and cost). None the less, Noveske went out of their way to get an upper to me in a timely manner. Their upper arrived with a barrel break in instruction sheet and a Noveske embroidered hat, business card and military manual. John Noveske was another to request a barrel break in. Theirs was the only upper, to my knowledge, that came in with non traditional rifling. Their octagonal rifling, as I understand it, will increase muzzle velocity and extend barrel life. A couple things other stainless match barrels do not boast and I believe should be noted. Noveske uses a custom marked rail made by SWS. The SWS rail is not one you see as often as LaRue, Daniel Defense, KAC or others. Many people who saw the uppers questioned whose rail it was and why they did not use a more well known brand. The only thing I dislike about the rail is its many, many lightening cuts. The rail also skips some grooves at the rear and in the center which can make the use of some rail covers (like Magpul ladder bars or XT panels) marginally problematic. Other than that, I find it to be a very nice rail which provides a continuous top rail. It is very slim in profile compared to many of the other rails, and it incorporates a mount for a QD sling swivel at the 31st rail at the 3 and 9 o’clock. The rail was marked 5.56 which is odd for a 6.8 gun, but my presumption is John wanted to get an upper in the test and may not have had a rail marked 6.8 to use. I believe a customer purchasing a 6.8 upper would get a rail marked 6.8.

The gas key was properly staked and the bolt used an extra power extractor spring with black insert and rubber O-ring.


The M4 feed ramps were smooth and perfectly aligned.


The gas block used a single pin in addition to a set screw that looked to be counter sunk into the barrel.


Upper/hand guard: CMT upper with Noveske marked SWS rail.
Barrel: 16” Stainless, bead blasted, octagonal rifling
Gas block and length: Stainless Vltor gas block with Noveske logo. Single pin, single set screw
Gas system: Mid length, direct impingement
Muzzle device: AAC Phantom
Bolt group: CMT
Charging handle: standard
Sights: Noveske marked Troy front and rear
Price for Package: $1511 (price would include tango down panels)
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STAG 5H

Stag’s 5H model was the last to arrive on 7/13/07. I had tried to get an upper from them via phone and email on at least two occasions. After not getting any response, I dropped it. 1_AR_Newbie however was more determined than I. He kept on the phone with them until they were tired of hearing from him and agreed to send an upper. It’s thanks to him and only him their upper was included. Their upper came with an aluminum C-Products 25 round mag, and military manual and Stag catalog. I was glad this upper came, even if it was late. As the most affordable upper and the only one set up in a very basic configuration, it would provide us with an extreme basic to very high end examples of what is available.
Fit and finish are what I have come to expect for a stock item. The standard hand guards fit a little loose, but then again, I have never seen a pair that weren’t. The exterior of the upper was a little dry and could have used an oil of some sort, but these are things I have come to see on bone stock uppers from about any manufacturer.

The gas key was poorly staked and the bolt used a standard power spring with blue insert.


The upper lacked M4 feed ramps of any kind.


The inexpensive aluminum gas block used dual clamping screws.


Upper/hand guard: Stag upper, standard M4 profile hand guards
Barrel: 16” Chrome lined
Gas block and length: Double clamp aluminum railed gas block
Gas system: Mid length, direct impingement
Muzzle device: A2
Bolt group: Stag
Charging handle: standard
Sights: none
Panels: none
Price for Package: $525


Abreviations
YHM = Yankee Hill Machine

Y NM Chrome = Young Manufacturing's National Match Chrome Carrier

Extractor:
std. = standard spring
extra = extra power spring
blk = black insert
blue = blue insert
O = O-ring
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BREAK IN!!


Before shooting for groups, I wanted to break in all the uppers. A few of the companies either directly requested a break in period or I had heard hinted that they would like a break in period. Therefore, I decided to break in every upper unless the maker specifically told me break in was not required. I used a 50 round break in for those uppers that were had it. 1 shot and clean for 5 reps, 2 shots then clean for 5 reps, 3 shots then clean for 5 reps, 4 shots then clean for 5 reps. I’m sure many of you who break in barrels may use a more extensive process, but I felt this was ample to do what we needed to get done and is probably better than many people will do.

ChuckJaxFL and 1_AR_Newbie were with me on the first break in day. Breaking in uppers is not a lot of fun. 50 rounds of 6.8 ammo is not a load of money, but no ammo is cheap anymore, and 6.8 is hardly the cheapest. Add to this the time and effort it requires. All of the above lead to a pretty long conversation relating to what someone might pay to have their upper broken in by someone else. I had mentioned how some of the uppers we received said no barrel break in was required, but I also mentioned how MSTN’s upper was the only one to have come broken in already, with test targets showing several sub-moa groups at 100 yards. It was not unnoticed that the only upper that had arrived already broken in was the most expensive upper in the mix. We discussed the price difference between some of the uppers and what we would have been willing to pay any of the companies to have the upper come broken in at the time of delivery. If you take a look at some of the prices, you could easily close the gap between many of them and the most expensive upper, which was already broken in.

Aside from this, the break in process with uneventful. I used my own Grenadier Precision 6.8 lower with standard trigger, a Magpul CTR stock and H buffer. I topped each of the uppers with a Trijicon TA01. I used Remington’s 115gr MC round (R68R2) in my own steel 25 round PRI mag with a Magpul Ranger plate. To clean I used Hoppes #9 Copper Solvent, the bore guide and rod that MSTN provided with a .270 brush, jag and Pro Shot patches.
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FIRST ATTEMPT AT 100

I acquired 1,000 rounds of Remington’s 115gr Core Lock Ultra Bonded PSP (PCR68R4) and hit the range on 7/08/07. Wow, that was very frustrating. The plan was to shoot 4 separate five round groups through each upper. I was unable to achieve anything under 2moa out of ANY of the 11 supplied uppers. I viewed that as a fantastic waste of time, money (the ammo is very expensive) and ammo. People have mentioned this ammo is geared more towards hunting than accuracy, and that may very well be true. But 1-AR-Newbie and myself half joked that we hoped whatever it was you were hunting had better be big, and close. I am still trying to return 600 rounds of this to Remington.


I should add we our first “malfunction“. The guns never stopped running, but during the shooting, when I tried to remove the magazine from the lower, it would not budge. One of the rounds jammed into the front lip of the magazine and bent it outward. This bend prevented me from removing the magazine from my lower. Again, there were no failures to feed or stoppages. Nothing. But the mag would not eject. I separated the upper from the lower and tapped the front edge of the magazine until it straightened out. It was fine after that.


For al accuracy testing, I used my Armalite M15A4 lower with a KAC 2 stage trigger, H buffer and SPR grip. I topped the upper with a Nightforce 3.5-15 optic in a LaRue SPR mount.



MSTN
1st group: 3 1/2”
2nd group 3 3/16”
3rd group 3 1/4”
4th group 3 1/2”

Ko-Tonics
1st group: 3 3/8”
2nd group 3 3/8”
3rd group 3 3/16”
4th group 3 1/4”

Global Tactical
1st group: 1 3/8”
2nd group 2 7/8”
3rd group 2”
4th group 3 1/8”

Barrett
1st group: 3”
2nd group 2 ¾”
3rd group 2 7/8
4th group 2 3/8

LWRC
1st group: 3”
2nd group 3 1/4”
3rd group 2”
4th group 5 1/8”

I only shot these 5 uppers. I gave up even trying this ammo at this point. Cost on this ammo is unbelievable and I felt like I had just wasted a day, about 150 rounds, and a lot of money.

Enter Art at Silver State. Art at Silver State Armory had posted in the original thread that he would donate some 6.8 ammo to the test. I tried to take him up on the offer a few times, but I could never get through to him. I left messages with his business partner, who said I would hear back from him. Sadly I never did. 1_AR_Newbie had been on the range the day we had so much trouble with the Remington ammo. He took the initiative, immediately got on the phone and tracked Art down. Art sent out 1,000 rounds of their 115gr OTM Enhanced Fragmentation round at what was a very, very reasonable price. It took a couple weeks to get it all here, but once it got here, out ammo troubles were over.

John at Noveske did what he could to get us hooked up with Hornady as well. I spoke to a couple Hornady people via email about the testing and what was happening. There was initially some response, but it died off shortly after our initial correspondences. My last email to them said I wanted to make sure they got my last message telling them what I was looking for and that we had some money to pay. They replied saying they did get the email, and that they would get back to me when they could. I didn’t hear back from them.
__________


MORE AT 100

Back to the range for 100 yard groups with the Silver State ammo. We immediately noticed a substantial difference. From the first upper to the last, we were getting much better groups, though not everything was shooting as well as I think they could by possibly trying some different ammo. Because of the big waste of money on the Remington ammo, I was forced to cut back the groups I would be shooting to only 2 separate 5 round groups though each upper.


It was at some point during this day I had a problem with one of the uppers. I could not get my LaRue SPR-M4 mounts (LT-104) throw levers to close on the PRI top rail. No matter how far I loosened the levers, they would not close. This is the PRI rail that attaches to the guns upper receiver and joins the flat top and the PRI tube. My answer was to simply take the top rail off. Once I removed this rail, I was able to put the scope mount on the Colt receiver the PRI upper was using.


MSTN
1st group 7/8”
2nd group 1 1/2” (4 of 5 shots within 1/2”)

Ko-Tonics
1st group 1” (4 of 5 shots within 1/2”)
2nd group 1 1/2” (4 of 5 shots within 1”)

Global Tactical
1st group 7/8” (4 of 5 shots one large hole)
2nd group 1”

JTAC
1st group 1 1/2”
2nd group 1”

Barrett
1st group 1 1/4”
2nd group 1” (3 shots in one large hole)

PRI
1st group 1 1/8”
2nd group 7/8”

LWRC
1st group 1 3/4”
2nd group 1 1/4”

LMT
1st group 1”
2nd group 1 1/8”

AR15barrles.com
1st group 1 1/2”
2nd group 1”

Noveske
1st group 7/8”
2nd group 7/8” (4 of 5 shots 1 large hole)

Stag
1st group 1 3/8”
2nd group 1 3/8” (3 of 5 in one large hole)
__________


ON TO 300


I was surprised that all of the uppers shot so similarly at 100 yards. I have done a fair bit of shooting at 100, 200, 300, 500 and 600 yards, so I knew that moa or sub-moa at 100 would not immediately equate to the same results at longer ranges. I suspected some of the premium barreled, FF uppers would maintain good groupings, while some of the chrome lined barrels with might start to open up at this distance. While this was the case as the targets show, the difference between them was still not dramatically substantial.

We set up at 300 on 9/09/07 and continued using the Silver State 115gr OTM Enhanced Fragmentation rounds. I experienced a magazine related malfunction during the 300 yard groups. MSTN included a 15 round PRI magazine with their upper. It was a used magazine they suggest I use because they knew it to be reliable. I used it throughout all the previous accuracy testing without issue. I had, however, been bringing one of my own PRI 15 round magazines as a back up. It was at this point I began using the back up mag (which looks identical to MSTN’s I had been using all along). I loaded the rounds into this back up mag while shooting the PRI upper and had a failure to feed. I took a note of the malfunction and continued to shoot the same mag in the Stag upper. Another failure to feed. At this point I took a closer look and saw that I had started to use the back up mag. I switched back to the original mag MSTN provided and had no other malfunctions for the rest of the accuracy testing.


MSTN
1st group 3” (4 of 5 shots inside 2”)
2nd group 2 1/2” (4 of 5 shots inside 1 3/4” and 3 of 5 in one hole)

Ko-Tonics
1st group 5 1/2” (4 of 5 inside 3 3/4”)
2nd group 6 3/4” (4 of 5 inside 3”)

Global Tactical
1st group 2 3/4” (even spread)
2nd group 3” (even spread with two touching)

JTAC
1st group 3” (even spread)
2nd group 2 5/8” (3 of 5 inside 1 1/4”!!)

Barrett
1st group 3 3/4” (even spread)
2nd group 3 5/8” (even spread but two shots were in one hole)

PRI
1st group 3 1/2” (even spread)
2nd group 3” (even spread)

LWRC
1st group 4 1/4” (4 of 5 shots inside 2 5/8”)
2nd group 4 3/8” (4 of 5 shots inside 1 3/4”)

LMT
1st group 4” (pretty even spread)
2nd group 4 7/8” (4 of 5 inside 3”)

AR15barrles.com
1st group 3 7/8” (4 of 5 shots within 1 5/8”)
2nd group 3 7/8” (4 of 5 shots within 3 1/16”)

Noveske
1st group 3” (4 of 5 inside 2 1/8” with 3 shots in one large hole)
2nd group 3 3/16” (4 of 5 inside 2 3/4”)

Stag
1st group 5 1/2” (even spread)
2nd group 6” (even spread)
__________


650 YARDS?!?

There was some discussion about whether we should push ahead to this longer range or not. It was suggested that we try it at 500, and I was open to that idea. However, when we arrived to the range on the morning we would shoot, we were told targets had to be put at the berm and no where ahead of it. This pushed us beyond the 600 yard line. From firing line to berm was something like 647 yards with a laser range finder. If that’s all we were allowed to do, that’s what I would shoot.

We set up 2 B8 bulls eye targets which measure 24”x24”. With a spotter I would shoot at a spot on the berm to get an initial sight in. It was surprising to me how much variation there was between one upper and the next. Sometimes as much as 8 to 10 moa difference in uppers. I’m not sure why this happens between two guns that are set up so similarly, but I’m here to tell you it’s a fact.

650 is a pretty long way


Looks like the Noveske upper


MSTN
1st group 5 5/8” (even spread)
2nd group  7 3/8” (3 of 5 shots inside 2 7/8”)

Ko-Tonics
1st group 8 1/2” (even spread)
2nd group 12 1/2” (even spread)

Global Tactical
1st group 16 ¾” (3 of 5 shots inside 4 1/2”)
2nd group 13 1/4” (even spread)

JTAC
1st group 15 1/4” (even spread)
2nd group 17 1/8” (3 of 5 shots inside 5”)

Barrett
1st group 22” (even spread)
2nd group 14 15/16” (3 of 5 shots inside 7 1/16”)

PRI
1st group 15 1/2” (3 of 5 inside 7 5/8”)
2nd group 12 3/4” (3 of 5 inside 5 1/4”)

LWRC
1st group 13 1/2” (even spread)
2nd group 10 1/4” (even spread)

LMT
1st group 10” (even spread)
2nd group 15” (3 of 5 inside 6 7/8”)

AR15barrles.com
1st group 11 1/2” (even spread)
2nd group 9 1/2” (even spread)

Noveske
1st group 7” (even spread)
2nd group 8 1/3” (even spread)

Stag
1st group 22 1/3” (even spread)
2nd group 15 3/4” (even spread)



Final thoughts on the accuracy testing. I can’t stress enough how the accuracy testing I did is a very incomplete and casual evaluation. I was fighting lots of mirage and bright sunlight on my 300 yard range day. The 650 yard range day was windy and somewhat rushed. I used only one type of ammo, I shot only two 5 shot groups per upper. None of this is anywhere near what one might have to do to get a true feel for what these guns are really capable of.

What I can say for sure is those guns which used muzzle brakes made accurate and precise follow up shots much quicker and easier. The difference is substantial. I wish could have documented what shooting the guns in reduced light would have been like. I would imagine those guns with flash suppressors would have shown their advantage then. If you aren’t much worried about what the gun shoots like in reduced light, guns with muzzle brakes are an easy choice.
__________


FULL AUTO

I must admit this was probably the most fun we had during the testing. 1_AR_Newbie was there along with RAM12375 and AEM, both long time members who post very infrequently. RAM12375 allowed me to borrow his Bushmaster lower with his registered drop in auto sear. The lower was equipped with Advanced Armaments Cyclic Rate Reducing buffer, a standard M16 trigger and LMT SOPMOD stock. I topped the uppers with Aimpoints new M4 on a LT659 throw lever mount.

We only shot 20 rounds through each upper in controlled bursts (some were more controllable than others!). We used the Remington’s 115gr MC round (R68R2) in the 30 round steel mag Barrett supplied with their upper for the full auto testing. We set up a 24” x 24” B8 target up at 15 yards and went at it.

Several uppers came with semi auto bolt carriers. Those uppers that came with full auto bolt carries were used as is by just popping their upper on RAM’s lower. I used the full auto carrier provided in the Noveske upper for those uppers that did not come with a full auto bolt carrier. I only replaced the bolt carrier, and we retained the original bolt, cam pin firing pin, and firing pin retaining pin. AR15barrels.com upper was spared from this test by his request (even though his upper came provided with a f/a carrier).

PRI’s upper was also excluded from full auto testing. This is the day that the PRI upper stopped working. After we changed the carrier (theirs was a semi carrier) I put the upper on the lower and pulled the trigger. One short burst then nothing. I looked, cycled the action and tried again. One shot, then nothing. Again, same thing. Again, same thing. We pulled the carrier out, looked around, and didn’t really see anything. I lubed it a little more, cleaned out the camber, and tried again. Same thing. I decided to move on to the next upper.

PRI gun malfunction



While I moved on, 1_AR_Newbie decided to see if he could put the original bolt group back in and try it on his Colt lower, in an attempt to isolate the problem. No luck, same thing. We were clearly having some sort of gas problem, but I did not want to stop testing to analyze it then and there.

The next day I went in to work and discovered the problem pretty quickly. The gas block had shifted forward slightly. Not much, but it was enough to get the barrels gas port and gas blocks opening out of alignment. I loosened the two clamps (they were not VERY loose, but they weren’t tight either) enough to move the gas block back into position. I test fired another mag and the problem was cleared up.

The PRI upper was one of two test uppers to use that gas block (JTAC’s uses it as well). I use this gas block on my own 16” 6.8 gun, my own AR10, and my own MK12 Mod0. I’ve used it on countless other uppers I’ve built for people. I don’t think there is an inherent problem with the gas block itself. But I think it does illustrate how gas blocks using clamping or set screws have the potential to slip. It probably doesn’t happen often, but it happens. I’ve seen it at least one other time when a friends double set screw low profile gas block came loose during a EAG class I was attending. I’ve heard KevB mention here that he has seen it happen as well. Now we had it happen to us during the 6.8 testing. Are set screw or clamped gas blocks unreliable? I wouldn’t go so far as to say that. I will, however, say that I think a pinned block is more secure.

MSTN gun on f/a


JTAC gun on f/a


Barrett M468 on f/a


vv VIDEOS LNKS HERE vv
Ko-Tonics full auto video

LMT MRP full auto video
^^ VIDEOS LNKS HERE ^^

MSTN
Gun cycled fast, my notes say “waaaaaay smooth!!!” 19 of 20 shots fell within 9 7/8”.

Ko-Tonics
Gun cycled pretty slow making it hard to manage. 19 of 20 shots were on target and fell within 14 3/8”.

Global Tactical
Gun cycled pretty slow and felt hard to control. 20 of 20 shots were on target and fell within 17”.

JTAC
(used supplied carrier)
Gun cycled slowly and felt wild. 19 of 20 shots were on target and fell within 19”.

Barrett
Gun cycled slowly, but still felt smooth. 15 of 20 shots were on target and fell within12 1/2”

LWRC
(used supplied carrier)
Gun shot slow and had the most uncontrollable feel. 18 of 20 shots were on target and fell within 9 1/4”.

LMT
Gun cycled quickly and felt good. 19 of 20 shots were on target and fell within 11/ 5/8”.

Noveske
(used supplied carrier)
Gun shot quickly and felt manageable. 20 of 20 shots were on target and fell within 16”.

Stag
Gun cycled fast and felt pretty manageable. 19 of 20 shots were on target and fell within 8 1/8” pattern.

Final full auto thoughts.
The Aimpoint was not sighted in on any of the guns. Several uppers would have easily had 20 of 20 shots on target had the Aimpoint not been sighted in so low. I have no clue what makes some uppers cycle fast, and what makes some cycle slow. We discussed the possibility of barrels with looser chambers shooting slower than barrels with tighter chambers? We wondered if twist rate could have something to do with it? The truth is I have no idea? But I do know that uppers which had faster cyclic rates were much easier to keep on target and control than those that cycled slow. Barrels with muzzle brakes again showed their value. Even the slower cycling Barrett still felt controllable with its 4 port muzzle brake. The MSTN upper with its QC brake was like nothing else we shot. I don’t know why or how? The chamber? The twist? The guns overall balance? I have no idea? But it was very smooth and controllable.
__________


Final-final thoughts on each upper:
(listed in the order they arrived)

MSTN

If I was hard pressed to pick one out as the winner, I would have to give the go ahead to MSTN. In my mind, and based on the results I had, none of the uppers stomped any of the others. However, MSTN’s upper kept being mentioned throughout the test. Theirs was the only upper to us on time with everything I asked for and extra. Their upper was mentioned multiple times during the break in portion of the test. It was already broken in and came with test targets to show this specific uppers accuracy potential. If one upper seemed to have inched ahead in the accuracy testing, it was MSTN’s.  I’ll be the first to admit we did not do enough accuracy testing to say theirs is anything close to being scientifically proven to be the most accurate. It could very well be coincidence that their upper did the best in two of the three accuracy tests we did. I don’t know, I just know what I saw and shot. With the differences at 100 being so close, theirs was one of only two uppers to place 3 shots of a 5 shot group through one large hole (Noveske being the other). The MSTN upper clearly turned in the best 650 yard groups. Their upper was the hand down most controllable under full auto fire. The difference between their upper and everyone else was dramatic. Even other uppers that used muzzle brakes instead of flash suppressors, weren’t as smooth to shoot. Performance wise, if any one upper did better than the others, the edge seemed to go most consistently to their upper. As the most expensive upper in the mix, I think you should expect something extra. I think MSTN, both as a company and the upper they provided delivered extra.
__________

KO-TONICS

It’s hard not to really take notice of this upper. When compared to the $525 Stag upper, this $742 upper offers you a free float rail, flip up front sight, mid length gas system, M4 feed ramps, and a barrel with what seems to be the more desirable twist rate and chamber. It is affordable, reliable, and accurate (turning in one of the best 650 yard groups!). Dealing exclusively in 6.8 product, Ko-Tonics seems to be among the some of the better informed dealers with respect to the round, its chamber and the barrels used to shoot them. Unknown to me before this test, Ko-Tonics upper was a great surprise, using a chrome lined barrel and an entry level free float rail, they never fell behind in any of the accuracy testing. Based on its price point and very respectable performance, I feel their upper clearly represents the best value of everything submitted, and everything I am familiar with for that matter.
__________

GLOBAL TACTICAL

Denny’s upper was a real performer and among the top contenders. Priced hundreds less than the most expensive uppers sent, I was surprised to see it use among some of the very best quality parts available. LaRue Stealth upper, gas block and 13.2 rail, Y/M bolt carrier, a premium barrel made this among one of the best fit and finished uppers in the test. I mentioned earlier the upper came with the first set of foliage green ladder panels I had seen, that’s always cool! I liked the QD sling attachment point utilized at the rearmost part of the 3 and 9 o’clock positions on the LaRue rail.  The advantages of this upper did not stop at its looks and feel. Global Tactical’s upper shot the best groups using the Remington load I couldn’t get any of the guns to shoot! It only narrowly missed showing the best groups at both 100 and 300 yards. Of the heavy hitters involved in the test, Denny’s listed his entry at a mere $1339 delivered. Only the Stag and Ko-Tonics upper came in at less money. This is a GREAT upper for that money, and I honestly think it would go for quite a bit more.
__________

JTAC

Another top contender throughout the test. Fantastic fit and finish, with a beautifully blasted barrel and Vltor’s billet upper. Priced near the top end of  the spectrum, it’s not unrealistic to expect as much. Aesthetically, I happen to really like mid or full length gas blocked uppers that use gas block flip up front sights, making JTAC’s one of my favorites. I don’t think I am alone in this, JTAC’s upper was among those I received the most questions and comments about while at the range shooting, and while they sat on the display wall at my shop all these months! Using the Daniel Defense M4 rail and ladder panels, it had a solid yet slim (not skinny) feel and balance while shooting offhand.
__________

BARRETT

I’ve mentioned it before, and I’ll say again how glad I am that Barrett their M468 upper. As one of the first companies to take the dive into the 6.8 market, I would have really felt badly if theirs was left out. The M468 has a lot of hardcore features I often look for in my 5.56 carbines. A mid-weight, 4150 chrome lined barrel with a double pinned gas block offers a lot of reassurance. Their 30 round steel mag was used exclusively throughout all of the full auto testing and ran 100%. I’m sure their use of the ARMS SIR turns a lot of people off. For years I was a big fan of the SIR family of rails. I agree that the last 4 years has seen great advances in the FF Rail market, and it’s hard for me to say the SIR would continue to be my first choice. It is worth mentioning that two of my oldest 5.56 rifles still wear SIR rails (a #58mod and a #59) and have seen more than ten thousand rounds over literally dozens of competition and classes, all without trouble. Even with its chrome lined barrel, the M468 remained accurate from 100 out to 650 yards. Carried by many major distributors used by gun shops all over the country, the Barrett M468 will be one of the most commercially available uppers as well.
__________

PRI

Even with the couple problems I had with the PRI upper, I would not hesitate to suggest them or their products to others. I’ve used them on numerous occasions, and have never had issues before. I was not expecting to have problems with fitting the scope mount on their rail, maybe if someone else has had this issue they will post here. Short of hearing more problems with that, I think it could be viewed as a fluke. Their gas block shifting was unfortunate, but illustrates the advantages of pinned gas blocks. PRI offers this same gas block set up with four set screws as opposed to two clamping screws. I believe this might be a stronger option when used with a barrel that has dimples cut to match the set screws of the PRI set screw model. Either way, with its match barrel and MSTN QC brake, their upper was smooth shooting and accurate throughout the test. I should note that a PRI 15 round steel mag was used for all of the accuracy shooting, and a 25 round PRI mag was used for the break in period of uppers. Both without a single feeding problem. (My personal 15 rounder had two failures to feed however).
__________

LWRC

As the only piston upper in the test, it kind of stands alone in some ways. I really like their rail, especially when compared to the rails on other piston uppers available. It has the slim profile of the best FF rails available for direct impingement guns, and has a removable top rail for barrel maintenance. I still worry how prudent it is to put a flip up front sight on this removable top rail, but being set up with a barrel mounted front sight, I have no results to substantiate this concern. The piston gun lived up to its claims and absolutely ran cleaner and cooler than anything else I shot. 1_AR_Newbie actually took the bolt group out of the upper after our full auto testing and held it in his hand to see if claims made by some piston supporters were realistic. They were, the bolt group was cool and easy to handle even after a few mag dumps (I let a few people shoot this upper on full auto to see if it was just me who thought it was wild). The gun ran noticeably cleaner and while I did clean its bolt group every time I cleaned  uppers, it was clear the LWRC bolt group was not in need of cleaning. I believe I could have run this entire test and never once felt the need to clean their carrier and bolt. I don’t know enough about gas systems and how they work to know if the piston is what caused the gun to rock us so hard during full auto shooting, but I have been told by people who seem to know better than me that it may have been the piston gas system that created so much push. What I like can sometimes be strange, in fact I may like something just because it is strange. Hitting the range with 11 uppers at a time causes people to ask questions and I was often asked which was my favorite. I typically have to pause and think before I would answer a question like that, but in truth, I think I like this upper the best. Not because it’s the most accurate (though it was accurate), not because it shot the best on full auto (it didn’t), but because of what it is. What it is, was different than everything else while being the same. Reliable and accurate, it did everything the others did, but did it different. I like that. Their piston system runs clean and I like that (cleaning 11 uppers sucks!). I like its rail, I liked the GG&G front sight with the bayonet lug, I liked the Matech rear sight, I liked the markings on the upper. I liked about everything about it.
__________

LMT

The MRP has always fascinated me. I’ve owned one for some time now, although I do not have a 6.8 barrel for mine. Each MRP I have seen (I’ve seen quite a few) has had exceptional machine work and finish. With 3 different caliber barrels (5.56, 6.8 and .204) available in different length as well as chrome lined and stainless, owning a MRP has gotten better and better as each year passes. With the coming of their piston barrel, the best may be yet to come. The first and true continuous rail upper gives you all the room you could want or need to mount any sight combo you need. Even uppers which use rails that mount flush with the flat top receiver offer limited solid mounting area. I avoid adding optic to even FF rails that lock up tight. When running a back up iron with a dot sight and magnifier, space can run from being tight to insufficient. Scopes with extended eye relief can also be difficult to mount on standard AR uppers. None of this is a concern with the MRP. Rails like the top rail that came with the PRI upper, or the one offered by ARMS accomplish extended mounting area, but not without raising your mounting platform which prohibits co-witnessing of certain optics (like the EoTech). Like the Barrett, the MRP comes with many features I look for in a durable, general purpose 5.56 gun. 4150 chrome lined barrel with a pinned bas block. Gun came with their dual extractor improved bolt and its rail incorporates QD sling swivel points at the rear most portion of its 3 and 9 o’clock rails, which I find nice. The MRP is pricey, but its quality and modularity make it one of a kind and well worth the asking price in my opinion. The gun performed well throughout the test and was another chrome lined barrel that allowed exceptional accuracy among most of the premium grade barreled competition. Great upper!
__________

AR15BARRELS.COM

Using a truly custom Krieger premium match barrel with LaRue 13.2 rail, its surprising to see this upper coming in at under $1400. Randall appears to be a pretty busy guy making custom barreled uppers by hand, one at a time. I expect my upper may have been put together in haste in hopes of not being too late for the deadline (a “deadline” that wound up being meaningless). This may have been the cause for the loose hand guard nut on the LaRue rail. Anyone with a vice, receiver block and a strap wrench could fix it in about 15 seconds, but not everyone has these tools. Above and beyond this, I have not heard of any other issues regarding Randall’s workmanship or assembling abilities. So again, I take this instance as a “fluke“. I have a Krieger barrel on an MK12 Mod0 clone and I must admit, it took some time before the barrel really started showing its true potential. AR15barrels.com’s upper was certainly accurate, but I feel like it will continue to become more and more accurate as the barrel is shot (and cared for).
__________

NOVESKE

Like Barrett and LMT, Noveske heard about this 6.8 round up late in the game, but rushed to participate and get an upper to me. I don’t know a lot about barrels, rifling, etc, but what I understand about the Noveske barrel makes sense. If I am in error, I will let others hash the details out, and I’m all ears. But Noveske’s match grade stainless barrel offers rifling that does not use lands and grooves. Its octagonal rifling offers a better fit between bullet and barrel, allowing less gas to escape. Less escaping gas increases velocity, increased velocity increases effective range and decreases bullet drop. The lack of lands and grooves in a barrel can possibly increase a barrels max effective life. All of this sounds great and are things none of the other entries can claim. Better velocity and longer barrel life are important considerations to me. They may be to you too. Taking a back seat only to MSTN’s upper in the 100 and 650 yard accuracy department, and just hardly coming in 3rd at 300, I’d put the Noveske in at second place if I had to place anyone, and not just for its performance in the accuracy portion. With so many uppers running so even throughout the evaluation, the Noveske upper stood out on more than one occasion for more than one reason. It arrived in a timely manner, was expertly finished and assembled.
__________

STAG
Widely available and priced at $525, this upper is honestly what will be the best selling 6.8 upper of the group, and its hard to argue why it shouldn’t be. At 1/3 the price of the majority of entries, this gun shot as well as the best of them at 100 yards. 100 yards is as long as the great majority of shooters will get the chance to use their uppers. I don’t know why, but this was probably the second best shooting gun on full auto. It cycled fast and was quite controllable. It did not provide great results at 300 or 650, but to be honest, 300 yard groups weren’t bad, and it at least turned in groups at 650. I honestly wasn’t expecting to get groups on target at that range, but was surprised that it didn’t throw a shot. While it lacked M4 feed ramps, and had a poorly staked carrier, I did not experience a single malfunction using any of the three types of ammo. I’d probably replace the gas block if I were to get this upper. While the one on the test upper was fine, I have had to replace a cracked Stag aluminum gas block on someone else’s gun before. While I still view the Ko-Tonics as the better value, this is a lot of upper for $525.
__________


And that’s all I have. Thanks to everyone listed in this article for helping me with everything. You think it took a long time to get this out? It would have taken longer had it not been for their generous help. Special thanks to Mike (1_AR_Newbie). He must have been with me on about every range trip ready to do whatever. Staple target, open ammo, load mags, prep uppers, tell me I suck and can’t shoot! Thanks bro!

Thanks to PolyTeckKID for his work on the charts, he took it on himself to compile them with the help of RedFalconBill and MSTN, and I think they ad a lot to the report. Great job!

All of us really owe a special thanks to everyone who kicked in for ammo. Mark LaRue and KevinB first and foremost. Had it not been for their and everyone’s generous donations, we would not have had the ammo we needed, or money to pay for everything associated with the test.

I’d also like to thank XM radio’s Classic Punk Rock radio station. It has been playing non-stop for all the time I have been playing at the computer writing this. There was some really great old songs playing that kept me tapping at this damn keyboard!

I'vegot some more pics and videos I will put up. But I have got to go to sleep. I am in pain!

So you didnt fall asleep at the keyboard after all...


Regarding the cyclic rates..... it appears that the difference could be between the carbine length and midlength gas systems. The carbine length systems in the test seem to be the ones that cycled faster based on your comments, which would make sense.

And yes, I was there when the AR15barrels upper came in with the loose Larue rail, fwiw.

Holding my spot with the distinction of being the very first non-Floridian to post.

Hmmm, there were three (3) uppers that averaged under a minute-of-angle out to 300.

GTS / Denny - .907
Noveske - .894
PRI - .9975

Depending on the accuracy of measurement, Denny and Noveske are a 1st-Place tie to the 300 yard line.

Kudos to all three.



ML

New-arguy, I KNOW how much work goes into a in depth review.  Fine job and thanks for the hard work and also a thanks to the folks who helped you!

Vic

Edited, this review of course should be tacked

Thanks NAG for all your work and time put into this eval.  A little more later but just wanted to get in a thank you before I head out to take my daughter to school.  Excellent write up!

J

Wow, that is an in depth review. Nice work.

AWESOME REVIEW, WELL DONE!

Great Job Neil!

FOR 6.8 SPC FAQ's and more see the link in AR  Variants HERE

Great stuff man. If you ever find yourself in Arkansas, I'll buy you a beer or 6(.8)for all the hard work.

The MSTN upper holding sub MOA at 650 yards is incredible. Not surprising based on their quality, but still incredible.

Thanks for the review neil, and all the hard work that went into it.

Having said that, I am disappointed with the accuracy portion of the report.  My customers most commonly report getting half-inch groups right out-of-the-box, such as this group that I shot by accident (meaning I was just sighting-in my 18" upper for hunting, and got this group):


Or this five-shot group from a customer:



Generally, if a customer calls and he isn't able to keep all his shots inside 1" at 100 yards, I ask him to send it in to be checked out.  There have been very few cases of this, and all with the stainless barrels that I no longer sell.

Sorry to whine, but again, I am disappointed.

But that's okay, I understand that there was a lot of pressure to get the shooting done, so I guess allowance must be made for this sort of thing.

Tim, Im sure that given the opportunity to try different loads in the guns, I could have eaisly cut 100 and even 300 yard groups down substantially on all of the uppers.

Neil, did you have any help shooting or did you shoot all the groups, in one sitting?

Jason

Excellent work -- thanks Neil.

Now I guess I need to get into this 6.8 thing...

Finally got a chance to sit down and post a couple of things.  Again, thanks to Neil and all those who took their time to shoot, take pics, donate time and money to the test.

My gas key looked ugly, but worked.  When I submitted this upper that's a test carrier I had on the bench, but not one I would send out in a new upper for a customer, and all the other bc groups I had in stock were spoken for, for builds.  I now build all my CMT Carriers here and side stake the keys.

As for feedramp misalignment:  An m4 extension, is an M4 extension.  Sometimes they align perfectly, sometimes they align not perfectly.  I didn't read about any of the ones that weren't beautifully aligned jamming or misfeeding  I would imagine that all the ones used were manufactured by one of two vendors and they were mixed throughout.  

As for accuracy, I'm happy with the accuracy achieved with my upper in the evaluation at 100, 300 yards.  The 650 yard accuracy sure isn't anything I would have hoped for and seems strange that things would open up that much, but I would venture that weather conditions might have played a part.  Either way, kudos to those who did well at 650.  

BTW Neil, I hope you didn't take offense at my question about the number of shooters.  Just curious if you ever got any help shooting, and I didn't see it mentioned in the thread.

Jason