? For the MK12 Clone Experts Out There???

[CrowCommand]

yeah you’re right. Thanks for reminding me Shipping is taking an eternity with Optics Planet right now. I just cancelled that order and ordered the stuff through PRI. Their shipping is typically pretty fast.

Any sign of that hand guard shipping? I put my order for a Gen III in this morning, wondering when I will see it....

 

[HogsLife]

Any sign of that hand guard shipping? I put my order for a Gen III in this morning, wondering when I will see it....

tracking says it’ll be here today

 

[CrowCommand]

tracking says it’ll be here today

Speak of the devil, I just got my shipment notice.

 

[HogsLife]

Speak of the devil, I just got my shipment notice.

PRI’s awesome. They and WOA are the vest I’ve seen with shipping

 

[CrabsandFootball]

Also, a Geissele SSA trigger is the most correct trigger you can get for a semi auto.

Actually when these guns were being made and into the early 00's, the SSA didn't exist. The Hi Speed with DMR spring would have been the correct trigger.

That build list is wrong. Some of the early guns may have had KAC 2 stages but the Hi Speed quickly replaced it as it was a much more reliable trigger. KAC later on redesigned their 2 stage into a much more reliable trigger.

 

[AMTGMC]

This was a complete PRI build, then I changed a few thing so don't beat me.
Changed out stock, added High speed DMR trigger and MK5 HD in Spuhr mount.

May not be as correct but it works.

@200yds

 

[RyanScott]

Actually when these guns were being made and into the early 00's, the SSA didn't exist. The Hi Speed with DMR spring would have been the correct trigger.

That build list is wrong. Some of the early guns may have had KAC 2 stages but the Hi Speed quickly replaced it as it was a much more reliable trigger. KAC later on redesigned their 2 stage into a much more reliable trigger.

The Mk12 I handled had an SSA I believe. Felt like it. Could have been a high speed. Wasn’t an SSF, the auto sear was removed.

 

[USMCSGT0331]

You guys seem to be missing the Wilcox top half ring mount for the Insight MRDS.

aka 'The Unicorn'

Lol, the Wilcox mount is common compared to legit patent pending marked Gasbusters, Recon Nav Spec marked NF scopes and first gen Ergo grips. Vero Beach rails are a pain in the ass to find as well.

Here's some other rare parts:

Minute discrepancies with trivial pieces such as bipod mounts and sling swivel mounts (there's a few different types)

Peq2 mounts are pretty hard to find

A few original takeoff barrels floating around

True clone builds aren't easy, most of your time is spent doing research and hunting parts

 

[Casca174]

Gents ... I hope you enjoy this! I came across a bunch of pictures of an original MK12 Mod 0, Gen 3, my team got in '08; brand spanking new in the deployment case. The inspection tag is dated '03. We had two other well used Mod 1's and a Mod 0 all with a couple of layers of paint but when we got this one in, I took a bunch of pics before the Weapon's guys painted it. Something I haven't seen often on MK12 Mo 0's is the Armalite symbol on the front of the magazine well, the long rail on the bottom of the forearm, and a trigger that's standard looking rather than a KAC or Geissele.

 

[Casca174]

More pics! Enjoy!

 

[HogsLife]

More pics! Enjoy!

dude that’s an absolute gold mine of info in those pictures!!! Thanks man! Awesome!

 

[Nikiel09]

Thanks for posting those pics man! I sent you a PM.

 

[_Windrider_]

So who has a copy of the operators manual?

 

[LanceCriminal86]

I usually post over on Arfcom only, but it seems I need to branch out a bit more as there's a lot of end-users over here. I'm a self professed Mk12 nerd so I figured I'd drop in with what I've researched and I'd love to compare with what y'all observed during your time in.

As far as receivers, it's been said before but the early pattern SPRs, before the Mk12 designation in 2002, definitely were seen with Colt AF forge marks, and Armalite forge with the AR and cross-in-circle mark. The Armalites seem to be on the darker/blacker color spectrum, but some of the Colt AFs I've seen some photos of look much lighter gray. It's been written that Diemaco uppers got used too, and I know I've seen them on some of the later ones like posted above (Gen 3 parts). It's possible when some of them were first photographed wear and UV exposure maybe ligtened them up, but many of them like this rifle, you can see a whole hodgepodge of grays compared to the stark black of the Leupold and Colt stock/grip.

As far as lowers, you've already mentioned GM Hydra and Colt, but there were also H&Rs in there as well. I have a case with an H&R SN on it, and I've seen snippets of old inventory sheets and other cases with them as well. That being said, you'll see dark almost black lowers that went through Anniston Depot in the 70s or 80s, usually with the ANAD and date stamps on the ejection port side of the magwell, while you'll also see much lighter grays on receivers that didn't get that rework. The Marines it seems got lowers even that looked like our boot camp A2s: almost silver.

Once the Mod 1s came in, some used Armalite uppers again and the Colt AF forge marks too, but later on most were Colt with the "Keyhole" coming later on. The photos SMGLee got peepee smacked for show that upper on a contract Mod 1.

The Mod 0s with Gen 3 bits, I know some had Diemacos and another I've seen with a Colt AF. With them supposedly only being made for a short time, and Casca174 showing theirs was inspected in 2003, those may be it for the receivers. By the time they were supplied I think Crane or whoever was doing them under contract (Maj Jiga or PRI direct?) weren't using Armalite any longer. Another thing I've seen: Almost all of the later Mod 0s I have photos of still had the A1 grips and Colt D style stocks with solid butt and articulated sling swivel. It seems Crane was out of A2 grips and E types or they just sent them straight out.

As to you @Casca174, thank you for posting those. There are not a lot of photos of the real late Mod 0s floating around, because as far as I can figure not as many were made before Crane decided to cease building or ordering them in favor of the Mod 1. The fact it was inspected in 2003 really helps me as I've had a hard time detemining when that revised variant started being supplied, since the Mod 1 seemed to have been in development later 2001 or early 2002, and was type classified in June? 2002.

And, you also helped solve another mystery: I have never seen a late Mod 0 in a case until today, and it looks like the same foam as the Mk12 Mod 1. I have a case that is a hybrid of the Mod 1 foam and the early SPR foam, so I'm still wondering which Mod was in it.

One last thought, you mentioned standard trigger. Before the KAC was chosen, Accuracy Speaks triggers were also tested earlier in the program, and were later used on some of the "Mod H" guns built for MSG Holland. If that trigger wasn't a KAC, Accuracy Speaks, or Geissele SSF (which may be possible as I think he didn't mark his old triggers the same way as now), I think maybe they did just send the rifle out with the lower as-is off the donor A1.

 

[Casca174]

LanceCriminal86 ... I didn't even know what I had in those pictures. I remember taking them but during this lockdown, I decided to start an early MK12 Mod 0 build. I scanned through some old files photos because I always took pictures of all the weapon systems for classes when I was cadre at the SF Weapons Committee in the early 2000s. I was actually looking for my old pictures for reference because I knew I had early versions of the Mod 0 from my Weapons Committee days when I discovered the series of photos I posted. The MK12 Mod 0 I posted was managed by Dave Textor's (R.I.P) my old Weapon's Sergeant so when I saw those pics, I decided to go with that build instead of an early version.

FYI ... That picture that's watermarked by adcofirearms.com, I'm sure I'm the original photographer ... haha. No complaints though, it's good to see the pic because those are the exact pictures in my cluster media files I'm looking for. It's definitely in the old SF Weapon's Detachment/light side classroom. I can tell by the layout, the mats, my old table the MK12 is sitting on, and the center beam at the back end of the table ... way before the move to the big Armament Facility.

One exception to my upcoming build, I have a Colt AF upper I was going to use but I happen to have a complete M4 upper built on a circa 2000 Colt/Diemaco receiver. I corresponded with Colt Canada and they confirmed my receiver was from the 2000 era so I'm going to dissect my Diemaco upper for this upcoming build and use it on the clone build since I can't recall seeing any MK12 clones with Diemaco uppers.

 

[Casca174]

So who has a copy of the operators manual?

TacticalDillhole ... I may have a copy. I need to cross state lines this weekend to dig through some of my junk for this confinement hobby. I figure it's a good time to get out of the cave and road trip. I'm working on finishing up and M24 SWS and starting this MK12 Mod 0 clone and I've got some of the smaller bits and pieces in a storage unit I have over there (Idaho). I think I have a manual but not sure. If I can dig one up, I'll post pics.

 

[LanceCriminal86]

Dude, I'm building my early gun on a Diemaco as well! A very nice light gray/purple anodizing on it, lots of character. And Gen 3s definitely had the Diemaco uppers so you're double good.

I need to shoot you a PM, I have a ton of pics I've scraped over the years from various forums, Instagram, etc. I always assumed that rifle was an early one because 1) classroom and 2) it has some set screws in the handguard which stick out from all the rest of them. I've seen 3 different variations of that first pattern SPR, ones with no set screws or button screws near the barrel nut/collar, some with 3 button head screws, and some with 4. USMCSGT0331 has one of the VERY early ones with tan Kal-Gard on it that KG Coatings did, while the rest like the one in the pic I posted (your pic apparently) they coated just the handguard in Kal-Gard flat gray, which now is KG Gunkote 2403F. I'll be having mine built up with that coating before it gets spray painted to match a last surplus FSB I managed to coax from PRI. Also they added the button head screws because they seemed to find that when they coated the handguards and baked them, the epoxy that holds the threaded insert in the tube started coming undone. So button heads were added to secure and help keep the whole thing in place. Honestly the ARMS rail is the only thing keeping those early ones together, as trying to get ALL 3, the barrel nut, handguard tube, and then collar to time their gas tube holes together makes for a pretty wonky setup. The Gen 3 basically took a similar approach to KAC and Armalite's tubes by just having two index pins in the handguard tube and sliding it on, then having the collar tighten it to the barrel nut.

And I will tell you, the early guns to get right is nigh impossible anymore without a LOT of fabrication. PRI doesn't have any more of the parts laying around, they've been used over the years for various builds. The barrel nuts just dried up within the last month or so, same as the "Gen 2" handguard collars. I got some of the last old top rails with the lugs for the ARMS rail, and they didn't have any more of the rear shorter ones. No more old side rails either. I'm having a new tube scratch made, and I managed to acquire a Gen 2 rail with an original PEQ top rail. I had the collar put on a lathe by another clone nerd who just put the grooves in it for me.

When it's all done, it's going in a case that came from ODA 535, will have a lower that matches the SN from the inventory sticker that's on it (H&R lower, rollmarked 80% by russianpaint), and hopefully by the time I'm done foam to go with it. Even exploring a custom AEM5 suppressor with the SN off the case to match.

I've got one last part evading me though: the PRI Gasbusted with the "Pat Pend" engraving on it that USMCSGT0331 mentioned above. A few guys have them and nobody's parting with them, and they had a head start looking. It's the last bit I need and off it will go to get NP3 coated like the originals.

Enough jibber jabber though, here's some pics of the project:

Before I sent the handguard parts off:


Handguard collar with grooves added:

Hanguard scratch made tube in progress:

How it's sitting right now waiting for everything to come back:

 

[Casca174]

Dude, I'm building my early gun on a Diemaco as well! A very nice light gray/purple anodizing on it, lots of character. And Gen 3s definitely had the Diemaco uppers so you're double good.

I need to shoot you a PM, I have a ton of pics I've scraped over the years from various forums, Instagram, etc. I always assumed that rifle was an early one because 1) classroom and 2) it has some set screws in the handguard which stick out from all the rest of them. I've seen 3 different variations of that first pattern SPR, ones with no set screws or button screws near the barrel nut/collar, some with 3 button head screws, and some with 4. USMCSGT0331 has one of the VERY early ones with tan Kal-Gard on it that KG Coatings did, while the rest like the one in the pic I posted (your pic apparently) they coated just the handguard in Kal-Gard flat gray, which now is KG Gunkote 2403F. I'll be having mine built up with that coating before it gets spray painted to match a last surplus FSB I managed to coax from PRI. Also they added the button head screws because they seemed to find that when they coated the handguards and baked them, the epoxy that holds the threaded insert in the tube started coming undone. So button heads were added to secure and help keep the whole thing in place. Honestly the ARMS rail is the only thing keeping those early ones together, as trying to get ALL 3, the barrel nut, handguard tube, and then collar to time their gas tube holes together makes for a pretty wonky setup. The Gen 3 basically took a similar approach to KAC and Armalite's tubes by just having two index pins in the handguard tube and sliding it on, then having the collar tighten it to the barrel nut.

And I will tell you, the early guns to get right is nigh impossible anymore without a LOT of fabrication. PRI doesn't have any more of the parts laying around, they've been used over the years for various builds. The barrel nuts just dried up within the last month or so, same as the "Gen 2" handguard collars. I got some of the last old top rails with the lugs for the ARMS rail, and they didn't have any more of the rear shorter ones. No more old side rails either. I'm having a new tube scratch made, and I managed to acquire a Gen 2 rail with an original PEQ top rail. I had the collar put on a lathe by another clone nerd who just put the grooves in it for me.

When it's all done, it's going in a case that came from ODA 535, will have a lower that matches the SN from the inventory sticker that's on it (H&R lower, rollmarked 80% by russianpaint), and hopefully by the time I'm done foam to go with it. Even exploring a custom AEM5 suppressor with the SN off the case to match.

I've got one last part evading me though: the PRI Gasbusted with the "Pat Pend" engraving on it that USMCSGT0331 mentioned above. A few guys have them and nobody's parting with them, and they had a head start looking. It's the last bit I need and off it will go to get NP3 coated like the originals.

Enough jibber jabber though, here's some pics of the project:

Before I sent the handguard parts off:


Handguard collar with grooves added:

Hanguard scratch made tube in progress:

How it's sitting right now waiting for everything to come back:

haha ... You've got that elusive bore guide too! Damn! That's thing is going to be awesome! I'm already jealous! I haven't even really got started yet. Parts collecting now. The furthest I've made it is verifying I have the right Diemaco receiver, no bump ARMS #22 rings and rail, proper Leupold, and I just spilled for a Colt M16A1 retro lower ... ouch! I'm working on an M24 SWS right now that has me preoccupied; almost have that wrapped up. Make sure you get pictures posted with your Diemaco in plain sight when it's done. I have yet to see a Diemaco MK12 pic. Thanks for posting!

 

[USMCSGT0331]

This thread just got even better!!!

@Casca174, thank you for posting the pics and info, that really helps with the Mk12 knowledge base! Please post pics of your build in progress!

@LanceCriminal86, glad to see you over here sharing your knowledge! Your Mk12 is the most meticulous build I've ever seen, that's truly an unbelievable amount of work going into it!

 

[LanceCriminal86]

Hell, I'm here to soak up more knowledge really. I've got a laundry list of questions I've still never had answered.

And honestly the only reason I had a SH account before was because I was tracking down your upper. When I heard it sold I was trying to figure out where it went, then one day it appeared in the ARFcom thread. That's twice I missed one of those uppers where I just wasn't fast enough, and the other 2 times now it's just been cost.

I'll find a damn Pat Pend handle, it's just going to take more time, scrounging, and somehow beating y'all to it.

 

[USMCSGT0331]

I stumbled upon that patent pending charging handle about a year or 2 ago. The guy might have another, I never bothered to ask him. I'll shoot you his contract info.

Sorry about the upper, it was too good a deal to pass up!

 

[lord of war619]

Back From CLE it was a expensive but fun project, I always wanted to build a MK12 out of a Colt Grey Diemaco upper so when I found a prestine Diemaco Cerro Keyhole M4 upper the part hunt started, I actually had Compass Lake assemble this one and its beautiful, the marking on the upper are the just perdect

 

[lord of war619]

waiting on a Colt mag catch and bolt stop and this is one is done, yes I know I can inatall any milspec bolt stoo and mag catch but Im way too anal to do that, another one in the books beautiful grey mk12 , the scope does not have clone correct turrets on this one i know it was juat for reference

 

[Casca174]

Back From CLE it was a expensive but fun project, I always wanted to build a MK12 out of a Colt Grey Diemaco upper so when I found a prestine Diemaco Cerro Keyhole M4 upper the part hunt started, I actually had Compass Lake assemble this one and its beautiful, the marking on the upper are the just perdect

Lord of war619 ... Very nice! I'm glad to be seeing some Diemaco's coming out of the woodwork. I'm currently collecting parts for my build as well. I've got the same upper. I'm going to throw a Diemaco bolt in as well ... still Colt, right. haha. I was sitting on the upper for an M4 build and didn't think anything about it until I decided to do an MK12, so now I'm disassembling the top end of my M4 for the MK12 build.

 

[Casca174]

So who has a copy of the operators manual?

TD ... No luck on a manual digging through my junk. I have seen some MK12 Mod 1 manuals posted on eBay though.

 

[lord of war619]

Lord of war619 ... Very nice! I'm glad to be seeing some Diemaco's coming out of the woodwork. I'm currently collecting parts for my build as well. I've got the same upper. I'm going to throw a Diemaco bolt in as well ... still Colt, right. haha. I was sitting on the upper for an M4 build and didn't think anything about it until I decided to do an MK12, so now I'm disassembling the top end of my M4 for the MK12 build.

is it a grey upper? post some pics

 

[Casca174]

Gents ... I went through thousands of files I had from the old SF Weapons Committee ... no luck so far. Virtually every other weapon system but the retro MK12. I know I have detailed pics of some of the early SPRs/MK12s somewhere, so hopefully, I come across them but right now no good news. I did find three pics, one of which is has been floating around online but not the other two. All three of these I took in the old SF Weapons Detachment classroom, that's me sitting in the background and by the BDUs, you can tell this is early 2000's. Hopefully, these help out LanceCriminal86. I see the eagle inspection stamp on the front of the magwell. I talked with Armalite and they said that the inspection mark wasn't exclusive to them and couldn't confirm if they were the ones that built my team Gen 3 I posted earlier, but I have only seen these inspection stamps on Armalites. FYI ... I talked to A.R.M.S. Inc. as well and they said they plan on re-making the old A.R.M.S. #22 mounts without the 90-degree stops. They planned on doing it before the COVID19 stuff broke-out but got behind because of it. That might save some folks from paying premium prices on eBay or Gunbroker if you're willing to hold out.

 

[LanceCriminal86]

Seems like y'all got some of the first Mod 1s, seeing that TS30 on there. And I guess they just moved the scope over to the SPR for clasroom purposes? Seems like the suppressor was the one off the Mod 1 as well. And definitely black instead of gray.

I actually had my SPR parts coated in that KG gray by the way, it's their 2403F flat gray. I can't wait till the handguard is done to slap it all together, but I'm still short two old side rails and that gasbuster.

 

[lord of war619]

Tax stamp arrived today on my AEM5 11 months later!!

 

[Cageylaw]

I see the eagle inspection stamp on the front of the magwell. I talked with Armalite and they said that the inspection mark wasn't exclusive to them and couldn't confirm if they were the ones that built my team Gen 3 I posted earlier, but I have only seen these inspection stamps on Armalites.

That DOD acceptance stamp is from the base M16A1 rifle. Nothing to do with the SPR build. Thanks for posting the new pictures.

 

[Casca174]

Seems like y'all got some of the first Mod 1s, seeing that TS30 on there. And I guess they just moved the scope over to the SPR for clasroom purposes? Seems like the suppressor was the one off the Mod 1 as well. And definitely black instead of gray.

I actually had my SPR parts coated in that KG gray by the way, it's their 2403F flat gray. I can't wait till the handguard is done to slap it all together, but I'm still short two old side rails and that gasbuster.

That KG grey is going to look awesome! I'm excited to see it!

We had quite the crop of early SPRs/MK12s at the schoolhouse before the ODAs picked them up. Knowing what I know now I wish I would have taken detailed pictures of them all ... no two were alike. If I come up with more file pictures I'll be sure to post but right now, nadda. It seems I have pictures of every other weapon system but those. It was early in the fielding and I think we got all those early models because of being the schoolhouse. I didn't give it much thought at the time, other than another souped-up M16 because we had a lot of crazy stuff going on then and those early SPRs were Frankensteins.

About the bore guides again ... I really doubt those early SPRs we had, came with bore guides the more I think about it. I don't remember them even being in deployment cases but our later generations were in cases and included the bore guides we've all seen.

I've got other projects going on now but I 'm slowly collecting parts for my gen 3 build ... currently, I've got the proper #22 rings, scope, Diemaco receiver, etc. and I just picked up a retro Colt US Property marked M16A1 lower and an A.R.M.S. PEQ 2-3 rail. Every piece (mag catch, selector, etc. ) on that receiver is as black as the receiver itself, so I might change some of those newer looking pieces for some older grey retro components.

 

[lord of war619]

Finally 10 months later they are complete now

 

[Casca174]

That DOD acceptance stamp is from the base M16A1 rifle. Nothing to do with the SPR build. Thanks for posting the new pictures.

Cagelaw ... good to know. I've seen these stamps on sides of magwells but Armalites always seem to appear right on the front.

 

[LanceCriminal86]

That KG grey is going to look awesome! I'm excited to see it!

We had quite the crop of early SPRs/MK12s at the schoolhouse before the ODAs picked them up. Knowing what I know now I wish I would have taken detailed pictures of them all ... no two were alike. If I come up with more file pictures I'll be sure to post but right now, nadda. It seems I have pictures of every other weapon system but those. It was early in the fielding and I think we got all those early models because of being the schoolhouse. I didn't give it much thought at the time, other than another souped-up M16 because we had a lot of crazy stuff going on then and those early SPRs were Frankensteins.

About the bore guides again ... I really doubt those early SPRs we had, came with bore guides the more I think about it. I don't remember them even being in deployment cases but our later generations were in cases and included the bore guides we've all seen.

I've got other projects going on now but I 'm slowly collecting parts for my gen 3 build ... currently, I've got the proper #22 rings, scope, Diemaco receiver, etc. and I just picked up a retro Colt US Property marked M16A1 lower and an A.R.M.S. PEQ 2-3 rail. Every piece (mag catch, selector, etc. ) on that receiver is as black as the receiver itself, so I might change some of those newer looking pieces for some older grey retro components.

So according to my research, the Mod 1s should have started showing up early in 2002 as the whole SPR/A and SPR/B, testing two different optics. Does that sound about right, or were they already testing the KAC parts version in 2001?

Also, regarding that TS30 scope, some of the early Mod 1s that went out also had the ARMS #36 top rail sleeve on them, which is similar to the extended riser style #38 some of the prototypes used. Do you remember seeing any of these? I feel like had they kept the #36 S-EX or a #38 S-EX, there would have been less complaints about the Mod 1 as far as eye relief as you could mount the optics up in the same way as the SPR. And, you could use the same scope rings across the whole program instead of Highs on the Mod 1, and Medium on SPR/Mod 0:

I'm planning to build a "half assed" version of this one as it's the only Mod 1 that tickles my fancy to be honest. I'm not feeling like ponying $2500 for a TS30, I'd rather that big of a glass purchase be for the S&B on the M40A3 I'd like to do someday.

 

[WDN-K-9]

Looking good!

Mod H and Mod 1. Still waiting on AE for collar and brake for the H. Spun the Surefire in place so I could send a few in the meantime.

 

[Casca174]

So according to my research, the Mod 1s should have started showing up early in 2002 as the whole SPR/A and SPR/B, testing two different optics. Does that sound about right, or were they already testing the KAC parts version in 2001?

Also, regarding that TS30 scope, some of the early Mod 1s that went out also had the ARMS #36 top rail sleeve on them, which is similar to the extended riser style #38 some of the prototypes used. Do you remember seeing any of these? I feel like had they kept the #36 S-EX or a #38 S-EX, there would have been less complaints about the Mod 1 as far as eye relief as you could mount the optics up in the same way as the SPR. And, you could use the same scope rings across the whole program instead of Highs on the Mod 1, and Medium on SPR/Mod 0:

I'm planning to build a "half assed" version of this one as it's the only Mod 1 that tickles my fancy to be honest. I'm not feeling like ponying $2500 for a TS30, I'd rather that big of a glass purchase be for the S&B on the M40A3 I'd like to do someday.

I think we had few Mod 1s around 2003 but I don't recall whether the A.R.M.S. #36 top rail was on them or not. That extended A.R.M.S. rail over the KAC handguard looks VERY familiar though. We got a large crop of Mod 1s in late 2004, not too long before I left out of there. I think that was too late though. I took a similar series of the Mod 1's photos like the Gen 3 (still haven't found the pics) but I doubt they would reveal an extended rail.
Your half-assed version looks pretty badass!

 

[mcm308]

Is Mr. Brown still building uppers for HCS?

 

[LanceCriminal86]

Is Mr. Brown still building uppers for HCS?

No, he and Kevin have parted ways from what I understand. Based on what I've seen in some of the Mk13 related postings recently I wouldn't find that desirable any longer.

 

[CrowCommand]

What PRI gas block are you guys running? I see 4 different flip up sight gas blocks on their site. I'm guessing it's the one branded "the original"? G1 .750", cross bolt, with the elevation thumb wheel?

 

[kmcale]

What PRI gas block are you guys running? I see 4 different flip up sight gas blocks on their site. I'm guessing it's the one branded "the original"? G1 .750", cross bolt, with the elevation thumb wheel?

That all depends on what variation you are trying to build, wheeled for early SPR, non-wheeled for late mod 0. Cross bolt for early or late 0's are incorrect

 

[03duce]

Couple quick questions.I have a original MK12 take off barrel dated 9 04 and it has the flats cut into it for a PRI style front site gas block.
Did any of the early Mod 1 rifles use that setup with the KAC Handguard or if not what would be the correct handguard and front site gas block setup for this barrel

 

[lord of war619]

Couple quick questions.I have a original MK12 take off barrel dated 9 04 and it has the flats cut into it for a PRI style front site gas block.
Did any of the early Mod 1 rifles use that setup with the KAC Handguard or if not what would be the correct handguard and front site gas block setup for this barrelView attachment 7357782View attachment 7357783View attachment 7357784

I would not use that barrel on a mod 1 the cuts would not be covered by the mk12 gas block Im pretty certain I have never seen this barrel on a mod 1

 

[Cageylaw]

Perfectly fine for a Mod 1.... And that barrel in question WAS a Mod 1 or it wouldn't have paint in the front flat. The 04 Rev3 barrels I've all seen came from Mod 1s. Probably all through the same source.

The Rev3 barrels were used on both Mod 0s and Mod 1s. Later on they cancelled the flats for the PRi block. But pretty much all early Mod 1s had both the set screw "dimples" and flats, so build what you want.

 

[LanceCriminal86]

For the record:

These photos were posted over on Arfcom years back after a visit to Maj Vince Jiga's shop by the crew at ADCO. Maj Jiga (Ret) assembled a ton of Mk12s and uppers during the time the contract was alive. These are clear pics showing Mod 1s being assembled with flats on the barrel, I believe these were from 2004.

 

[03duce]

Thanks guys .That is some very useful info.I will build it into a Mod 1

 

[raysugar4567]

That all depends on what variation you are trying to build, wheeled for early SPR, non-wheeled for late mod 0. Cross bolt for early or late 0's are incorrect

So in order to use the set screw gas block you have to send a new Douglas barrel off to a gunsmith right? My Douglas SPR barrel from operation parts does not have flats.

 

[raysugar4567]

I've got one last part evading me though: the PRI Gasbusted with the "Pat Pend" engraving on it that USMCSGT0331 mentioned above. A few guys have them and nobody's parting with them, and they had a head start looking. It's the last bit I need and off it will go to get NP3 coated like the originals.

So are you saying the original Gasbusters were NP3 coated?

talked to A.R.M.S. Inc. as well and they said they plan on re-making the old A.R.M.S. #22 mounts without the 90-degree stops.

Really? This is great news I need Arms rings and having the correct ones would be great. I only wish they would make the SPR Swan sleeve again. I have the PRI sleeve but it looks much different. The PRI sleeve is black and the Swan rails above are gray. The screws to secure the rail to the upper are also on the wrong side. You guys sure have some great parts.

 

[kmcale]

So in order to use the set screw gas block you have to send a new Douglas barrel off to a gunsmith right? My Douglas SPR barrel from operation parts does not have flats.

Yup. ADCO does a good job

Ordered my barrel from CLE, shipped them my front sight, and had the flats milled before shipping out to me. You most likely have to send in a front sight for the job to be done, at least, I would think/hope a gunsmith would require that.

Here is my attempt at an early Mod 0 as it currently sits. Handful of things incorrect, a few things I still intend on addressing at some point as some of the discrepancies are beyond my ability to correct.

And just for shits and giggles, the Mod 1

 

[raysugar4567]

Here is my attempt at an early Mod 0 as it currently sits. Handful of things incorrect, a few things I still intend on addressing at some point as some of the discrepancies are beyond my ability to correct.

Nice! My Mk 12 mod 0 isn't quite correct either. I have the PRI top rail instead of the ARMS and a few other pieces that are not Colt. I'm most interested in finding a clone correct optic. I'm pretty sure every optic used on the Mod 0 is now discontinued. I saw a mark 4 3.5-10 in stock awhile back but it had the wrong turrets. I like your A1 stock. I have a Colt a1 grip on mine and the Sopmod stock but I am considering switching to the A1 if I can find a genuine Colt A1 in decent shape. I was lucky to find a few Colt c marked A1 grips awhile back in great shape.

 

[longshot2000]

Anyone got a line on a gen III PRI hand guard? Optics Planet seems to be the best price I can find at $282

I don't like trashing dealers, but some which you might have mentioned actually do not stock, and then go out and buy and ship. We have a full line of all things Mk12, and soon to be released Mk12 full deployment kits. We do offer some 'hide discounts. PM me for all things Mk12. The scope has limitations, and must be part of a build we sell