* * * * * * * * * *

The following parts lists and substitution parts was compiled by lancecriminal86 over the course of a LOT of research. Read up and pay attention!

Below are the 100% .mil-spec parts lists to build a true SPR or Mk12 clone. Some of these parts are no longer manufactured and will require much effort and money to locate through forums and online brokers. Keep in mind the rifles were built off donor M16A1s, hence the prevalent A1 parts in the lower receivers and the BCGs. They were also first configured using parts available from 1998-2004, and most are inferior in some ways to newer designs. If this bothers you too much, STOP NOW.

The rifles were issued as a kit in a Pelican 1700 case with cutouts. The kits included the rifle with suppressor, optic, bipod, an Eagle TAS-1 UMSS sling (unobtanium and also absolute crap), with a Dewey 1-piece cleaning rod plus Otis cleaning kit, and a cutout for magazines. An operator's manual was also included, however these have not been officially released for public consumption. However, the manuals are out there, and some companies building Mk12 uppers include one. Whether these are official .mil operator's manuals or specially made is currently unclear as the manual itself still contains language that it is not for distribution.

- Alternate .mil-spec parts due to NFA, NLA parts, or changes in name/markings for current production in [brackets]

- Extra notes about parts or availability are in (parenthesis)

LOWER
Lower receivers were standard across the SPR/Mk12 variants and the only variations would be between grips, stocks, and buffers. Most were marked either Colt or GM Hydramatic. All other parts were the same in regards to the lower parts. One caveat is the trigger, as the program originally selected the Knight's Armament 2-stage Full Auto Match trigger. Later on, some issues regarding negligent discharges occurred, and Geissele SSF triggers ultimately found their way into the Mk12 family. Whether 100% of all Mk12s eventually received the Geissele trigger isn't clear, so either is acceptable.

• Lower: M16A1 pattern [Nodak Spud NDSA1 or 80% re-profiled/finished/engraved]
• Trigger: Knight's 2-Stage Full Auto Match Trigger or Geissele SSF [KAC semi-auto Match or Geissele SSA/SSA-E]
• Grip: A1, A2, ERGO Original
• Stock: Originally issued with A1 stocks, both solid D and trapdoor E types; as A1 stocks dwindled, A2 were used; ModH rifles rebuilt with Ace SOCOM stocks
• Small parts: Standard M16A1 parts
  
  

UPPER
The upper receivers, which ultimately differentiate the four variants of the Mk12, have the most variation between each other.


Early SPR/Mod0

• Upper: Colt, Diemaco, or Armalite marked, flat top, M4 feed-ramps
• Barrel: Douglas 416r SS, 18" SPR contour, 1/7 twist, flats milled for PRi FSB (Compass Lake, Centurion Arms, High Caliber Sales, and PRi can all supply barrels that meet the appropriate spec minus FSB flats)
• BCG: Colt M-16
• Handguard: Precision Reflex Gen I carbon fiber free-float Handguard, rifle length (identified by button-head screws and one vent hole near barrel nut on lower half; no heat shields)
• A.R.M.S. #38 SPR MOD Sleeve (either the PEQ version or with uneven spacing on the front  but not the full 1913 railed version)
• FSB: PRi early folding front sight base and gas manifold, set-screw, with elevation wheel
• Charging handle: PRi Gas Buster M-84 with military latch
• Muzzle device: OPS Inc 12th Model brake/collar, and 12th Model suppressor [Allen Engineering AEM5 and brake/collar]
• Rear iron sight: A.R.M.S. #40
• Scope rings: A.R.M.S. #22 Medium rings, #22 Tactical Ring Cap and #22 Tactical Ring Rail (rings should not include "lever-stop" hump as produced later by A.R.M.S.)
• Optic: Leupold Vari-X III 3.5-10x40mm LR, M3 turrets, illuminated Mil-Dot reticle (use .308 turret) [Leupold LR/T 3.5-10x40 LR, M3 turrets, Illuminated Mil-Dot reticle]
• Bipod: Versa-Pod with A.R.M.S. #42, or a Harris with A.R.M.S. #32 (Versa-Pod far inferior to Harris)

Late Mod0

• Upper: Colt or Diemaco marked, flat top, M4 feed-ramps
• Barrel: Douglas 416r SS, 18" SPR contour, 1/7 twist, flats milled for PRi FSB (Compass Lake, Centurion Arms, High Caliber Sales, and PRi can all supply barrels that meet the appropriate spec minus FSB flats)
• BCG: Colt M-16.
• Handguard: Precision Reflex Gen III carbon fiber free-float handguard, rifle length
• A.R.M.S. #38 SPR-PEQ-2-3 Sleeve
• FSB: PRi folding FSB, set-screw, .750 (original production had PRi's full address engraved on sight tower; those engraved with "PRi USA" are later manufacture)
• Charging handle: PRi Gas Buster M-84 with military latch
• Muzzle device: OPS Inc. 12th Model brake/collar, and 12th Model suppressor [Allen Engineering AEM5 and brake/collar]
• Rear iron sight: A.R.M.S. #40
• Scope Rings: A.R.M.S. #22 Medium rings (rings should not include "lever-stop" hump as produced later by A.R.M.S.)
• Optic: Leupold 3-9x36mm TS-30, Mk4 MR/T 2.5-8x36mm TS-30A2, M2 turrets with Mk262 BDC, illuminated TMR reticle
• Bipod: Harris with either A.R.M.S. #32 or KAC RAS bipod adapter

SPR/A, SPR/B, Mod1

• Upper: Colt or Diemaco marked, flat top, M4 feed-ramps
• Barrel: Douglas 416r SS, 18" SPR contour, 1/7 twist, flats milled for PRi FSB (Compass Lake, Centurion Arms, High Caliber Sales, and PRi can all supply barrels that meet the appropriate spec minus FSB flats)
• BCG: Colt M-16
• Handguard: Knight's Armament M4 Match FF RAS, rifle length (now called the SR15/16 Match FF RAS)
• Gas block: NSWC Crane pattern (Badger Ordnance parkerized/NSN version is correct, has open front of gas tube hole)
• Charging handle: PRi Gas Buster M-84 with military latch
• Muzzle device: OPS Inc. 12th Model brake/collar, and 12th Model suppressor [Allen Engineering AEM5 and brake/collar]
• Scope rings: A.R.M.S. #22 High rings (A.R.M.S. rings should not include "lever-stop" hump as produced later by A.R.M.S.)
• Optic: Leupold Mk4 MR/T 2.5-8x36mm TS-30A2, M2 turrets with Mk262 BDC, illuminated TMR reticle or NightForce 2.5-10x24 (optionally with NightForce rings)
• Bipod: Harris with KAC RAS bipod adapter (BRM-S, A.R.M.S. #32 could still optionally be used)

ModH, Mod "Holland"

• Upper: Colt or Diemaco marked, flat top, M4 feed-ramps
• Barrel: Noveske 16" Recon, mid-length gas system, profiled for OPS Inc. 12th Model brake/collar (will require aftermarket contouring of most barrels)
• BCG: Colt M-16
• Handguard: Precision Reflex Gen III carbon fiber free-float handguard, FDE, rifle length
• Charging handle: PRi Gas Buster M-84 with military latch
• Muzzle Device: OPS. Inc. 12th Model brake/collar, and 12th Model suppressor [Allen Engineering AEM5 and brake/collar]
• Scope Rings: A.R.M.S. #22 Medium rings on PRi recce rail (rings should not include "lever-stop" hump as produced later by A.R.M.S.) or LaRue LT-104 SPR mount
• Optic: Leupold 3-9x36mm TS-30, Mk4 MR/T 2.5-8x36mm TS-30A2, M2 turrets with Mk262 BDC, illuminated TMR reticle, Leupold Vari-X III 3.5-10x40mm LR, M3 turrets, illuminated Mil-Dot reticle (use .308 turret) [Leupold LR/T 3.5-10x40mm LR, M3 turrets, illuminated Mil-Dot reticle]; S&B Short-Dot
• Bipod: Harris with either A.R.M.S. #32 or KAC RAS bipod adapter
• Iron sights: (apparently PRI were supplied but never used)
  
  

In the Wild
Naturally, once these rifles were issued to units, operators and even Marines used various non-issued parts. Here is a short summary of what has been seen:

Early SPR/Mod0:
Both Leupold 3.5-10x40mm and 3-9x36mm scopes have been used. Many have had carbine stocks like the old CAR-style, enhanced M4, SOPMOD Gen I, or even the Tactical DuoStock swapped on.

Mod1:
One 3rd SFG-issued rifle pictured with SSgt Robert J. Miller (MoH recipient) used an A.R.M.S #36 S-EX 5.56mm rail, and a Leupold M3X 10x fixed-power scope, possibly pulled from an M-24 or SR-25 rifle. Another has been seen with a Magpul PRS, LaRue mount, and a Premier Reticles 3-15x used by an AMU shooter, and a similar rifle was pictured on a FOB in a very posed-looking photo. Further, a USMC-issued Mod1 was seen using #22 Medium rings instead of High rings, and a LaRue mount has been spotted as well. Grips have varied from the usual A1, A2, and ERGO, and at least one Magpul MIAD has been used. As with the Mod0s, carbine stocks like the SOPMOD and M4 have been used on Mod1s.

ModH:
The Mod "Holland" was already a small-batch configuration, but even as soon as they were issued to 5th SFG units, some Ace SOCOM stocks were replaced with Magpul ACS and CTR stocks. Optics are basically anything existing in the unit's inventory, from S&B ShortDots still in the system, the 3-9x and 3.5-10x Leupold scopes from earlier Mod0s, and there's even a photo of an ELCAN on a Mod1 floating around. No non-magnified optics like EOTechs or regular Aimpoint M2/M4s, but Micros have been seen on offset mounts. Backup iron sights, as a whole, were almost entirely left unmounted. Grips were again the same usual selection.

Parts Alternatives for Clone Building
Many parts are rare, expensive, and/or both. Despite this, there are some alternatives to a 100% pure clone that will still provide the same visual look and performance. While not a museum-grade clone, most would be hard-pressed to discern the difference. Just know there are those of us out there that will haze and peer-pressure you into further moving your build towards a true clone.

Barrel:
Popular options are the White Oak Armament SPR barrel (rifle gas), BCM's SPR barrel, Rainier's Match and Ultramatch offerings (ensure it's the SPR contour with 12th Model profile), Ballistic Advantage's SPR barrel. Compass Lake Engineering can also spin a Mk12 profiled barrel with a Criterion chrome-lined blank, or even a Krieger, which was one of the original contenders for the program. The DPMS Mk12 barrels are NOT properly profiled for a clone.

Optics & Rings:
In the case of the Leupold 3-9x or 3.5-10x, it's generally okay to go for a non-illuminated version of either, sometimes with M1 or other turrets and reticles. As far as the NightForce scope, the 2.5-10x24mm is not generally released to the public anymore (with one recent exception through Sniper's Hide), so many use the 32mm or even 42mm versions with the #22 High rings. As for the rings, any of the recent produced A.R.M.S. #22s with the lever-stop humps are functionally the same, the desire for non-lever-stops is purely aesthetic when going for the most authentic look. As LaRue LT-104s have been seen in use, it is justifiable to use one depending on whether you have a specific rifle you want to copy, or even just if you absolutely cannot acquire #22 High rings.

A.R.M.S. #38 SWAN Sleeve:
The #38 family of sleeves are no longer available. Finding them secondhand usually cost $250-$300 easy, more for rarer early variants. Fortunately, PRi's copies of the sleeves look and function almost identically, with minor visual differences. PRi and other builders supply these currently for complete Mod0 builds.

FSB:
While the set-screw version of PRi's FSB is spec, most use the cross-bolt, clamp-style version. They are extremely robust, and when aligned and torqued, have been shown to hold strong enough that you'll probably shear your barrel extension pin or upper before it budges. This is mainly how Mod0 uppers are supplied by most vendors, including PRi themselves.

Suppressor, Brake/Collar:
Diverging from the OPS Inc. or AEM brake and collar will get you MAJOR flak. Trust me, I've been running an AAC SPR/M4 for years now and it took a LONG time to not get clubbed every time I posted it. The Allen Engineering AEM5 is basically the current production of the OPS Inc. 12th Model, as they were originally made by Ron Allen and his team in the first place. Only minor differences separate original OPS Inc. cans from AE cans, and these are only obvious to trained eyes.

As far as the rest, you can swap Colt parts out for any other .mil-spec parts, like BCM, DD, CMT, etc. Any billet uppers/lowers, funky BCG coatings, extended bolt releases, etc. are extremely frowned upon. Remember, once you start going down the path of building a "better" rifle rather than what was spec, you're quickly beyond clone territory and would have been better off building a custom 16" or 20" rifle. Cloning is generally viewed as all-in or not at all.

* * * * * * * * * *

Complete Mk12 Mod0 / Mod1 Uppers
Bravo Company Manufacturing
High Caliber Sales
Precision Reflex Inc.

Specific Mk12 Tech
Augee's side-by-side comparison of the original ARMS SWAN Sleeve and PRI reproduction PEQ Sleeves: bottom of p136
KOBK's side-by-side comparison of PRI Gen I, II, and III handguards, and Gen I and Gen II FSBs, and SWANs: middle of p137
Augee's Mod1 gas block tech: top half of p357
Glass1's Early Mod0 photo breakdown: middle of p449
tamboi's Leupold Vari-X, TS30, and TS30A2 scope history/lineage, and part numbers, p.792

Attached File

Dragging my ass with the pics:













ETA: don't think i'm gonna be shelling out $300 for NLS ARMS #22Hs.

Very nice

My guess is mark 4 2.5-8x36. By the time they went to the Holland that was the scope being used the most I think. Just a guess.

Might be a really stupid question but info on the barrel? I want a dark finish like this. CLE has coating options but I don't want to wait that long :/ lol

High Caliber Sales barrel

They can finish it in different shades?

That's 3.5-10. Many re-used SPR optics from old guns, hence the Medium rings and glass already painted. Lots of the Recce rail ones seem to use old glass in medium or other brand rings.

I've already spend a thousand dollars into this build and it can't even shoot #CloneLife

p/n A613 = Gen2/3 carbine length tube, as mentioned earlier:





...and the original (already sold - no PMs, please):

No, they do it to the same color that Crane used. It's basically KG gunkote

Looks like Barg-e-metal.

What a shit position.

Thanks. I need one of those tubes. I'm going to order the part number you listed. I have one ace tube that is so bad I'm not even going to show it here.

Also CLE didn't take very long at all to mill flats on my barrel and do the barrel coating. 2-3 weeks. I started reassembling my early MOD 0 upper last night with that barrel. The PRI gen 2 repro tube is a pain in the ass. I don't know who designed that nightmare but WTF!!? When I saw the baggie of 10 set screws I knew this would be bad.

I dont know how the original discussion of the ACE stocks went down but I found this thread from 2005.

http://www.ar15.com/forums/t_3_118/240223_.html


Only a few pics still show up, but the ones that do all have circle latches. So far its the earliest dated pics I can find that are time-stamped.

There was another thread from like 2003 but all the pics are gone.

https://www.ar15.com/forums/t_3_12/173515_.html&page=

I messaged user Coltm4 to see if he still had his stock or the pics. No go.

Here is a pic of another circle latch from an old page on another site



At the bottom the copyrighted date says "2001-2005" . That might not be accurate, but I feel its close.

Here is a pic that was posted in 2006



Again, another circle.

This was 2006 as well. I can't tell what it is




So far. The earliest timestamp I can find on the square latch is around the 2008-2009 time period.

I'll keep looking but so far it seems the circle was indeed the first gen. Can anyone timestamp any of the pics from the theater?

Well, that's because you've only spent $1000...that's just a start when it comes to cloning

I've got less than $1000 in my m16a4 clone, haven't bought the acog yet though....

-Kirby

A few more "2004-2005" images from Google; all showing the round latch and solid end-plate loop:






I am also seeing the square latch show up around 2007 (though one image was from 2006, below):




USAF Photo - Fort Bragg, Oct. 7, 2007:

USAF Image

The EARLIEST I could find of the square latch was this Saiga from 2006:


Saiga Link

May/June of 2006 appears to be the crossover point where people are posting recent builds showing both the round and square latch.  Prior to that, it was only round latch stocks.  You'll also notice that all 2007+ stocks with the square button use the sling swivel (or are not mounted on an AR).  This seems to indicate to me that the Gen 2 stock (square latch, machined loop) was a very limited run item (~6 months), probably only sold until the remaining sling loops from the Gen 1 stocks were depleted.

Case in point - 2 posts from mid-2006 showing round button stocks:

Build 1
Build 2

According to images I have of PRI certificates of authenticity for Mod 0 uppers (serial no. -2, -6, and -12) re-sold to the public, the rebuilds took place on or around April 2007.

I rest my case.

So opinions on this idea.... in the next couple days I'm going to run one of my scopes down to a laser etching place I just talked to who says they can duplicate the TS-30
  A1

And
TS-30
 A2

Markings you see on the side of the military scopes. They seemed pretty confident and it doesn't look to hard.
Attached File
Attached File

It won't look the same as the factory "Leopold" is centered on the Civy scope because there is no ts 30.  On the ts30 scope Leopold is etch higher up.

It's a Douglas SPR SS, turned by CLE.
The finish is "Parker Grey" Duracoat, which is pretty close to the KG Gunkote grey, spec-ed on Crane Bbls by HCS.

Thanks S-D, my payment along with a token of my appreciation sent!

Email sent requesting a total.

Thanks again for doing these.

I apologize for missing any emails. I'm trying to keep it straight. I only had 25 extra round count logs made. They are about gone. The extras that is. If you have already talked to me I have yours put aside. I'll count later and see how many extra are left. If there is a big enough demand I will have more made.

My man! Thanks for all you do. You really stepped up and made shit happen.  Now let's see them finished lowers...

Guys.... PLEASE DO NOT write messages in PayPal about gun related items OR that you are paying for goods and services with friends and family option. I appreciate all of your kind words and the extra dollars some of you have contributed. i can't express that enough. I also can't have my PayPal account terminated. Please be careful about that. I'm not calling anyone out publicly but I received a payment with a note that did both. I don't know how on top of that PayPal is. Hopefully it just slides by them.

Does anyone have any experience with this situation? Please email me. I'm trying to decide if I should just shut it down for a day or two in order to see what happens.

I'm going to show my ass here, but....

The only mk12 optics are:
Leupy 2.5-8x36 (3-9) M2
Leupy 3.5-10 M3
NF 2.5-10x24
NF 3.5-15x50

Correct?

My MK12 clone is finally complete.  A couple parts aren't exactly clone correct, but it'll do

-Kirby

The NF 3.5-15x50 was only seen a couple times in ITW photos. It wasn't a standard issued optic for any Mk12

Are M1 turrets kosher-ish?

I'm glad I bought my TS30 when I did.... Whew.

So I decided to go back to the A1....so waiting on more parts to come in and I found some colt ambi-safeties with the dual long arms on the ee so those should get here today. I'm probably going to hang on to the sopmod but if anyone is in desperate need of a gen 1 let me know. Anyway pic thread....I'll post some more up when the rest of my parts get here.

given up hope finding an ARMS #38 rail, 2 years of scouring EE and ebay

Keep at it....I found mine by luck. I happened to check the thread just as someone posted they had one. You never know what will pop up when, it gets discouraging but then it makes it a million times better when you find it. I will say the well seems to have gone dry on those.

Yet another part that I simply called A.R.M.S. with the correct part number and they had it as new-old-stock... I'm showing my hand here, but since I have no rare parts I'm currently hunting for, you'd be truly surprised how many 'unobtainium' parts I've easily sourced for Mk 12, Mk 14, and Mk 18 clones over the last 5-6 years by simply calling the manufacturer and talking to the right person.

What model number 38 though? Was it a peq-2-3 or a mod 1? The mod 1 is technically only correct for the 6.8 proto

They had the mod 1 rail that was all picitinny for awhile but are out now.

Those days of calling up the company and seeing what they have in the back are pretty much over for the MK12 stuff

yeah i just called, no luck lol

I had it happen to me and it was not caught by paypal.  I didn't close my account or anything, just took my chances and gave the buyer (newb) a stern warning for future purchases in the EE.  I think if you close it they may look and see it but you have to decide what's best for you.  Btw, gift $ sent with a nice note


Mahalo

I'm talking about really old stuff like the PEQ-2-3 without the Gen 3 cutout.

In late 2014 I directly ordered a "38SPR PEQ2-3" (Gen 3) and in late 2015 I ordered a "38SPRPEQ MOD-L" which is the PEQ-2-3 for Gen 1/2 hand guards.  All I had to do was send an e-mail and get the correct part no. sorted out.

As mentioned in the last page or two, I called up DoubleStar and ordered a square-latch carbine buffer tube over the last month.

I'm local to Crimson Trace and walked right into their HQ and bought an IR laser for a HK45C-T within the last year or two.

You'd be shocked what you can easily find when you stop assuming things are only available on the second-hand or grey market.

What's the consensus on running a non-illuminated 2.5-8x36?

Totally kosher. Seen in the wild on several earlier mod 1's

Negative, it's very subjective.

Those early ones had a unique housing for the elevation/windage turrets. It's not a blanket thing.

Are you talking about M1 knobs or nonilluminated 2.5-8?
M1 knobs are a no go PERIOD. they never have been accepted. I tried and pled my case for months because I found 3-9 with M1 knobs but never M3 knobs. I finally gave up when I found my first 3-9 with M3's. Now I just want TS30 on the side of my scope. Gotta figure that out. As for nonilluminated glass I thought there were some 3.5-10 scopes that were not illuminated in some pictures posted many pages back. On issued rifles. If you were running the fixed 10x it was not illuminated wasn't it?
I would like to find a nonilluminated 3.5-10 to go on my early mod 0. I've seen them at 600-700 in the EE but not lately. I just scored another 3-9 illuminated M3 so I'll use that instead. If I find the 3.5-10 I would need to get rid of something to make room. Everything has glass now.

Everything I find has M1 knobs

Thank you kind sir

Email sent for total payment.  No mentions here!!!!

Hell just my upper with no optics,rings, FH or BUIS was $920 in 2003.

Nice 80% lower, gotta get one and run it through my 5D jig. I picked up a KAC lower for
now.

Leupold will switch them for $130, mine is with them now.

Yep that's what I had on my personal MK-12 I took to Afghanistan in 2007. I knew one day someone would say mine wasn't clone correct
so I just post a pic and smile




How it looks now waiting on the 2.5-8x36 scope to get back from having the M1 knobs switched out for M2s at the leupold custom shop.

My old 3.5-10x is on my SR-25, I just realized My MK-12 is over 13 yrs old

Just looked at the FDNY rifle and I see what you're saying now. Thanks for pointing that out.