I consider myself fortunate to own not one, but two of the 16” Noveske Recon barrels with the mid-length gas system.  Both barrels have the medium contour with the Noveske gas block, which is secured to the barrel with one set screw and one taper pin.  Both are stainless steel with a bead-blasted finish and both have barrel extensions with M4 feed-ramps.  One of these barrels is chambered for the 5.56 X 45mm cartridge and the other for the 6.8 X 43mm SPC cartridge.

Both barrels are built with nearly identical upper assembly components.  Components common to both uppers include Colt M4 upper receivers and LaRue Tactical free-float handguards; a 9” handguard for the 5.56mm build and an 11” handguard for the 6.8mm build.  Both barrels are capped with a Smith Enterprise Vortex flash suppressor and both uppers use a Young National Match bolt carrier.











5.56mm build.






6.8mm build.












The 5.56mm Noveske barrel has a 1:7” twist and has Noveske’s proprietary chamber.  According to Noveske’s website:

"The Noveske Match Mod 0 chamber is designed to offer 100% reliability while retaining maximum possible accuracy. The chamber body is slightly larger than the 5.56mm NATO minimum, but within the 5.56 NATO tolerance. The throat is redesigned for proper bullet alignment with the axis of the bore. This chamber was developed to fire MK262 Mod 1 on AUTO in hot environments."

In previous accuracy testing with the 5.56mm barrel, I found the 77 grain Sierra MatchKings to shoot very well from this barrel.  Three 10-shot groups using hand-loaded 77 grain Matchkings fired from a bench-rest at 100 yards measured:

0.83”
0.95”
1.01”

When these three, 10-shot groups were over-layed on each other using RSI Shooting Lab, they produced a 30-shot composite group that had a mean radius of 0.28”

The 6.8mm Noveske barrel has a 1:10” twist.  The Noveske web-site does not give any other information on the nature of the chamber used in this barrel.  Muzzle velocities from Hornady factory loads using their 110 grain bullets run between 2530 to 2560 fps from this barrel.

Sierra makes a 115 grain MatchKing bullet for the 6.8mm SPC cartridge and it seemed to be the logical choice for accuracy testing with this barrel.  Using hand-loaded 115 MatchKings running at 2400 fps, I obtained three 10-shot groups off the bench from 100 yards that measured:

0.81”
1.06”
1.20”

These three, 10-shot groups were also over-layed on each other using RSI Shooting Lab to produce a 30-shot composite group with a mean radius of 0.30”.   Here are the two composite groups side-by-side for comparison.









The best 10-shot group from the 5.56mm build.






The best 10-shot group from the 6.8mm build.








5.56mm on the left, 6.8mm on the right.






77 grain SMK on the left, 115 grain SMK on the right.

Those are two beautiful builts.  Great accuracy from both.

How do you install a Larue handguard on a barrel with a pinned gas block?  Doesnt it get in the way?

Nice build.  I need to try out the 77grain bullets with my 14.5 Noveske.

nice, very nice

I have a pal that is bringing me a 16-inch 5.56 barrel from John's shop in two weeks.  
For free.

Quoted: How do you install a Larue handguard on a barrel with a pinned gas block?  Doesnt it get in the way? Nice build.  I need to try out the 77grain bullets with my 14.5 Noveske.

Install the barrel on the upper receiver.  Install the gas system.  As mentioned above, the handguard then slips over the low profile 0.750" gas blocks such as those from Noveske and LaRue Tactical.

Molon, were you surprised with the accuracy of the 6.8SPC?

It is a very small GB.


I have pics with a scale next to it, somewhere.

nice to know about other's grouping.shows the consistency.I used the 75 Grn TAP
just because of Noveske's recomendation.I would like to try a heavier and a light for comparison.I am not sure how it would compare with Molons because my Recon is an 8P.

and definately have to get one of the 6.8's

Molon,
You are a master.  Your posts rate a 10.  Photography a 10, graphs a 10.  I'm jealous of your guns, cameras and abilities with both.  In other words....Great post.

Quoted: Molon, were you surprised with the accuracy of the 6.8SPC?

Quite so!  I get all warm and fuzzy anytime one of my  AR-15s puts 10-shots into less than an inch at 100 yards.

Quoted: Molon, You are a master.  Your posts rate a 10.  Photography a 10, graphs a 10.  I'm jealous of your guns, cameras and abilities with both.  In other words....Great post.

Thank you kindly.  I really need to get myself a nicer camera one of these days, but there's this Schmidt & Bender Short Dot II that keeps calling my name . . .

Excellent post!

Molon,

I been thinking about building a 6.8 using the same exact barrel you have and mate it to a Vltor VIS middy.  

Have you shot your 6.8 out to distance?  like pass 500yrds? what is your impression on it?  

I intention is to replace my 308 AWP as an easier shooting, gun with less cost on ammo and the distance I shoot would be no further then 600yrds on steel.  

TIA.

Quoted: Chen, I took my 6.8 to a 'Long Distance' rifle course a couple of months ago, and I'll be taking it back for the follow on course.  Though I will say my rounds were not as accurate as Molons (my ammo would only produce 1" 10 shot groups). Hits on full-size silhouettes at 580 yards with the 6.8 was not a problem.  Note the JBM calculator predicted the 'come ups' exactly correct for the conditions as well (I printed out some range cards prior to the course).

I am on the right track.. thanks.

height=8

Quoted: I have a pal that is bringing me a 16-inch 5.56 barrel from John's shop in two weeks.   For free. how

Quoted: Molon, I been thinking about building a 6.8 using the same exact barrel you have and mate it to a Vltor VIS middy.   Have you shot your 6.8 out to distance?  like pass 500yrds? what is your impression on it?   I intention is to replace my 308 AWP as an easier shooting, gun with less cost on ammo and the distance I shoot would be no further then 600yrds on steel.   TIA.

I'm still just doing testing at 100 yards, but here's some interesting info about the 6.8mm SPC for distance shooting.  The 6.8mm SPC Hornady TAP factory load using the 110 grain V-MAX bullet running at 2550 from a 16" barrel has an almost identical trajectory to that of Hornady's 75 grain TAP FPD load from a 16" barrel.

Molon,

Thank you fro the info, can you keep me posted on your finding on the 6.8?

This is what I plan on doing.

I am going to send a LMT 6.8 bolt to mate with the Noveske mid length 6.8 barrel in 16inch, i am going to ask for the vltor gas block to be pinned on the barrel.

young Mfg carrier

PRI gas buster

then install the barrel to a VIS rilfe and bury the gas block under the handguard.

surefire 6.8 brake.

KAC BUIS F&R

LaRue SPR mount with Leupold 2.5-8x MRT.

I have a PWC lower with Accuracy speak trigger that has a Diemaco C7 stock on it.

Nice builds. I have a few Noveske barrels also, top notch accuracy across the board.

Quoted: Molon, Thank you fro the info, can you keep me posted on your finding on the 6.8?

Will do.

Quoted: I guess I didnt ask my question clearly: how does the barrel nut get over the pinned gas block?

Start with a stripped barrel.






Place the barrel nut into position on the barrel.






Then install your gas block.

Quoted: Quoted: I have a pal that is bringing me a 16-inch 5.56 barrel from John's shop in two weeks.   For free. I guess I didnt ask my question clearly: how does the barrel nut get over the pinned gas block?

You can knock the pin out and remove the gasblock.  The pin is similar to the std FSB retaining pins where they are tapered and can only can go in from one side.

Is your 6.8 polygonal rifling?

ah...thanks.  ive got the 14.5 noveske without the pinned gasblock.  i wondered what people did with the pinned gasblock - i didnt know it was removeable.  by this weekend it should look like a shorter version of Molon's but ill have to wait to get the FH welded up to shoot it.

Molon,

I am about to order the barrel, I have a quick question, what is the thread size of the 6.8 barrel on your rifle?  from the flash hider, is it 1/2x28R?

TIA.

Quoted: Quoted: I have a pal that is bringing me a 16-inch 5.56 barrel from John's shop in two weeks.   For free. I guess I didnt ask my question clearly: how does the barrel nut get over the pinned gas block?

It doesn't go over the gas block, you take the gas block off first.  

It's difficult to find a gunsmith that is set-up to perform this on a barrel.  That's why I wanted one pinned right off-the-bat, less hassle down the road.  

SMGLee,

My particular barrel is threaded for 9/16 x 24 and I'm using the appropriate Smith Enterprise Vortex flash suppressor for it.

tag......for future reference

I'm liking the 11" LaRue handguard on the 6.8mm build so much, that I decided to changed-out the 9" handguard on the 5.56mm build for an 11" handguard.



5.56mm build with 11" handguard






6.8mm build

Sweet!