Page 1 of 7 123 ... LastLast
Results 1 to 10 of 69

Thread: Mk12 Mod 0/1/H

  1. #1

    Mk12 Mod 0/1/H

    Ladies and Gentlemen, I have decided to embark again on a dangerous path, haha! As some of you may know, I went to the ends of the earth with my Mk18 Mod 0 clone build and the OCD got a little out of control there. I swore to myself that I would never attempt another clone build, especially on a range queen. Most of my shooting has been with my bolt guns during the last few years, so I’m not sure why I poured so much time and effort into the Mk18 build, but maybe it was just a bit of cabin fever mixed with some unanswered childhood desire to have a copy I saw in in some unremembered TV show or movie from the 90’s.

    http://www.canadianfirearmcentral.ca...459-Mk18-Mod-0

    Anyway, while doing researching on the Mk18, I stumbled on more than a few threads on the Mk12, but just tucked that away as an afterthought. Well, that god damned afterthought has manifested itself into an itch, and well, now I’m starting to scratch that itch. As with my previous build, I’m telling myself and all of you now that I am not going to go full retard like my other build. This one will more or less resemble a Mk12 of sorts, but I’m not out to make an exact clone. For anyone here who does have a clone, please feel free to post in this thread as I would love to see your builds.

    I’m not in a hurry to get this build done either, so it will be a long, slow process that I hope to keep under the wife’s radar.

    Anyway, here’s some info on the Mk 12 (blatantly borrowed from the interwebs) and hopefully I can start posting soon with some parts I’ve acquired towards a build.

    The United States Navy Mark 12 Mod 0/1 Special Purpose Rifle (SPR) is a rifle in service with United States Special Operations Forces in Operation Enduring Freedom and previously in Operation Iraqi Freedom. SPR initially stood for Special Purpose Receiver, but that nomenclature has been replaced as the weapon became a stand-alone weapons system, and not just an add-on upper receiver assembly (part of the proposed SOPMOD upgrades). The SPR was eventually type classified by the U.S. Navy as the Mk 12. Note that the weapon was developed by a Navy office (Naval Surface Warfare Center Crane Division) for SOCOM units, not for use by units that fall under the conventional US Navy.

    History

    The SPR, used by Special Operations Forces of both the U.S. Army and U.S. Navy, is a heavily modified light designated marksman variation of the M16 line of infantry weapons, chambered for NATO standard 5.56×45mm ammunition. The SPR concept was originally proposed by Mark Westrom, currently president of ArmaLite, while working at Rock Island Arsenal in 2000.[1] The program was an outgrowth of the desire by both US Army and Navy special operations forces for a rifle with greater effective range than an M4 carbine but still shorter in length than a standard issue M16A2/A4. The SPR program appears to have grown out of both the SOPMOD Block II program, and the U.S. Navy SEALs Recon Rifle (a 16" flat-topped M16 carbine). The Naval Surface Warfare Center, Crane Division expanded on the Recon Rifle.

    The exact history of the SPR is unclear, but there appear to be either four or five prime iterations of the rifle, culminating in the most recent Mk 12 Mod 1 version. One progression has four models: SPR Proto 1, SPR Proto 2, Mk 12 Mod 0 and Mk 12 Mod 1.[citation needed] The other progression has five models: SPR, SPR/A, SPR/B, Mk 12 Mod 0, and Mk 12 Mod 1.[citation needed] The specifications in this article follow the second progression.

    Different U.S. military service branches appear to typically deploy different iterations of the SPR. Photographs, including both U.S. Department of Defense photographs and privately obtained photographs, consistently show most U.S. Army Special Forces operators using the Mk 12 Mod 0, while NAVSPECWAR operators and U.S. Army Rangers have been identified as using the Mk 12 Mod 1 version.[2][3] In fact, Marcus Luttrell mentioned the fact that he carried a MK 12 during Operation Red Wings several times in his 2007 book Lone Survivor: The Eyewitness Account of Operation Redwing and the Lost Heroes of SEAL Team 10. Limited use was seen with the USMC.[4][5]

    Beginning in mid-2011, SOCOM began divesting the Mk 12 SPR from their inventory and replacing it with the marksman version of the SCAR Mk 17. The Mk 12 is to be completely replaced by 2017. [6]

    Specifications

    Upper Receiver: The majority of the SPR upper receivers were initially supplied by Colt, with others being produced by Diemaco (now Colt Canada). Colt had been outsourcing parts of its production to Diemaco for several years, then purchased Diemaco in February 2005. It is unclear whether the upper receivers for the later SPRs came solely from ArmaLite, or were a mix of receivers from ArmaLite and Colt/Diemaco. All of these upper receivers are flat-topped, but have been seen with either the old-style teardrop forward assist or the newer round style.

    Lower Receiver: When the SPR program was still just an upper receiver assembly (and not a complete rifle), Crane assembled all of its prototypes using either M16A1 or M4A1 lower receivers, because the full auto trigger group in these lower receivers provided a consistent pull while the more common 3-round burst trigger groups didn't. It is unknown whether this pattern continued as the rifle evolved. There is also some issue about whether, when the Navy type-classified the weapon, Precision Reflex Incorporated (PRI) began assembling the rifles themselves. While a number of trigger options were tried in the end, the Knight's Armament Company (KAC) 2-stage trigger was finally decided upon as the standard.

    Barrel: An 18-inch (457 mm) threaded-muzzle match-grade free floating stainless steel heavy barrel with a 1:7 (178 mm) rifling twist ratio is standard for the SPR.[5] The barrels are manufactured by Douglas Barrels with a unique contour that reduced weight but maintained rigidity for accuracy. An OPS Inc. muzzle brake and collar (to align the OPS Inc. 12th Model Suppressor) is installed with the barrel. These barrels were designed to take advantage of the new Mk 262 cartridge, which uses a 77-grain (5 g) bullet.
    Buttstock: SPRs have been seen with M16A1 or M16A2 fixed buttstocks, telescoping M4 buttstocks, and the Crane Enhanced telescoping buttstock. The rifles are compatible with any type of stock system developed for the M16.

    Handguards: In all cases a free-floating forearm is used, which does not touch the barrel directly. This increases the accuracy of the weapon by removing vibration and pressure exerted on the barrel by the rest of the gun. The first SPRs used PRI Gen I or Gen II carbon-fiber free-float tubes. The SPR/A, SPR/B, and Mk 12 Mod 1 all use the Knights Armament Company M4 Match Free-Floating Rail Adapter System, KAC part number 99167. The Mk 12 Mod 0 uses PRI Gen III free-float tubes. The Gen I and Gen II Freefloat Forearms are combined with the Atlantic Research Marketing Systems #38 SPR MOD Sleeve, while the Gen III Freefloat Forearm, due to its it larger barrel nut, only works with the ARMS #38 SPR PEQ-2-3.

    Sights: The original SPR used an early PRI flip-up front sight with an elevation dial, which has since been discontinued. The Mk 12 Mod 0 uses the current PRI flip-up front sight. The SPR/A, SPR/B, and Mk 12 Mod 1 use the KAC rail foreend flip-up front sight, KAC part number 99051. The SPR and Mk 12 Mod 0 use the ARMS #40 flip up rear sight. The rest of the models use the KAC 600 meter flip up rear, KAC part number 98474.

    Optics: Due to the relative modularity of the system, optics (as well as almost everything else) can be mounted according to the operator's wishes. However, SPRs are most often seen with a 3.5–10×40 mm Leupold LR M3 (SPR/A), a 2.5–8×36 mm TS-30 (SPR/B), or a 3–9×36 mm TS-30 A2 (Mk 12 Mod 0/1) Mid Range/Tactical Illuminated Reticle Dayscope. Night vision devices can also be attached. These scopes usually come with flip open dust covers and a honeycomb anti-glare anti-reflection device. Given Nightforce Optics' NAVSPECWAR contract, it is believed that many NAVSPECWAR issued SPRs will use the Nightforce 2.5-10x24 NXS scope.

    Mounts: A long accessory rail, called a SWAN Sleeve (ARMS SPR MOD or ARMS #38 SPR PEQ-2-3), manufactured by ARMS, is installed, running the length of the rifle. The SPR/A and SPR/B both used the KAC M4 Match FF RAS, KAC part number 99167. Two ARMS #22 Throwlever 30 mm steel rings are used to mount the dayscope. The SPR/A, SPR/B, and Mk 12 Mod 1 use ARMS #22 high rings, while due to the increased height from the SWAN Sleeve, the SPR and Mk 12 Mod 0 use ARMS #22 medium rings. An under-the-handguard ARMS #32 Throwlever mount is used to mount the Harris bipod (the ARMS #42 Throwlever mount is used to mount the Versa-Pod); this features a quick release action.

    Bipod: Originally the relatively expensive Parker-Hale swivel bipods were used, but were taken off the system after the initial SPR[citation needed]. Currently, a Harris swivel model bipod is typically used with the SPR, and is sometimes seen with a KMW Pod-Loc tension adjustment device.[5] As mentioned above, the bipod is mounted via an ARMS #32 throwlever device attached to the bottom rail of the rifle's forearm. The ARMS mount is used on both the Mod 0 and Mod 1.

    Suppressor: The OPS Inc. 12th Model SPR Muzzle Brake Suppressor threads directly onto the OPS Inc. muzzle brake and uses the collar to stay centered. In 2014, Ops, Inc stopped manufacturing this model of suppressors, and the equivalent product is currently manufactured by Allen Engineering Co. as the AEM5. It is substantially the same suppressor design and actually built by the same individual, Ron Allen, who previously fabricated the 12th model suppressor for Ops, Inc.

    Ammunition: The SPR is not used to fire standard issue 5.56mm M855A1 or M193 ball or M856 tracer ammunition.[5] Due to the limits in terminal performance and relatively poor accuracy of the 62-grain (4 g) M855 ball, the Mk 262 Open Tip Match (OTM) round was developed as a more accurate round for the SPR, and manufactured by Black Hills Ammunition. The first production batches were designated Mk 262 Mod 0 and used a Sierra Bullets MatchKing 77-grain (5 g) Hollow Point Boat Tail bullet without a cannelure (crimping groove). Black Hills then approached the Nosler bullet manufacturing company, who made a similar 77 gr (5.0 g) OTM bullet, and Nosler agreed to supply cannelured bullets to Black Hills. The newer load was designated Mk 262 Mod 1. Recently, Sierra added a minimal cannelure to its bullet, and this has since replaced the Nosler bullet in the current versions of Mk 262 Mod 1. In late 2014, Sierra introduced a tipped version of this bullet which adds a polymer tip to improve ballistics. This new bullet was found exclusively in an upgraded version of the Black Hills Ammo MK262 Mod 1 loading, but this bullet has been released by Sierra to reloaders prior to the end of 2014. The Sierra part number for this bullet is 7177.
    Mod 0


    Mod 1


    Mod H "Holland"


    Some words to live by from a level 5 clone master from ARF:

    Originally Posted By BurtSaun1049:

    These are the stages of clone. You are at Stage I. Hang in there, and you will progress to Stage IV:

    I: Clones are really cool, but I bet I can improve upon the design with an inspired build.
    II. I'm disappointed with my inspired build because it just doesn't scratch the itch and no one wants to see pics of my rifle. I bet I can sub out a few parts that are more expensive for cheaper options.
    III. Alright, why did I waste my money on those non-spec parts when I knew I wouldn't be pleased. I'll settle for a 90% build with some minor, non-clone subs.
    IV. Alright, I admit I am powerless to resist a spec clone, and I atone for my prior sins and building crap-tier builds that neither I like not anyone else wants to see. I will now build as to-spec as I reasonably can minus getting an M16A1 lower.
    V. All your clone are belong to me. I am ECPrevatte, destroyer of clones.
    Last edited by mister donut; 04-05-2018 at 04:41 PM.
    “The greatest happiness is to scatter your enemy, to drive him before you, to see his cities reduced to ashes, to see those who love him shrouded in tears, and to gather into your bosom his wives and daughters.”

  2. #2
    Out oh! I can see months of painstaking scrounging ahead on this one. I can see this getting expensive fast. The sights on the Mod1 look to be KAC so $300 just for the backup sights. Never mind the free float handguard etc. Interesting project. I look forward to seeing how this one goes. That MK12 thread was a really good read. Thanks for posting up the specifications per Mod. I'm not that familiar with these rifles.

  3. #3
    Member
    Join Date
    Apr 2015
    Location
    Surrey, BC
    Posts
    325
    I give you $200 for one of your kidneys to help you get start it.
    I am not an animal I am a human bean!

  4. #4
    Who are you trying to fool? You will go full retard on this one too. Wouldn't be right if it wasn't perfect.

  5. #5
    Quote Originally Posted by Full Metal Jacket View Post
    Out oh! I can see months of painstaking scrounging ahead on this one. I can see this getting expensive fast. The sights on the Mod1 look to be KAC so $300 just for the backup sights. Never mind the free float handguard etc. Interesting project. I look forward to seeing how this one goes. That MK12 thread was a really good read. Thanks for posting up the specifications per Mod. I'm not that familiar with these rifles.
    Lol, the scrounging has begun. I was really on the fence about which way to go, Mod 0 or Mod 1 and did a bit of research on what either will cost. Well, disappointingly, I’ve come to the conclusion that neither with be cheap if I go with 100% clone accurate. The best I can manage for now is “close enough” and I can probably get to “close enough” a lot faster with the Mod 1 look.

    PRI parts appear to be unobtanium in Canada, and there’s not a whole lot of hope for the rail, the PRI folding front sight post/gas block, sleeve and muzzle brake either. The only vendor that I could find in Canada that lists PRI is one I would rather not do business with.

    A complete upper from PRI may be the way to go instead of trying to source all the parts on their own. Looks like a complete upper from PRI runs about $1,600 USD which is a hard pill to swallow given the horrendous exchange rate. I’ll have to have a chat with Aztech Armories and see what it will cost to my door and decide if I want to go down that road one day.

    For now, I’ll probably pick up a few KAC parts and throw it together into a Mod 1ish look. What I’ve got so far isn’t even worth posting photos of, but I have an upper (the wrong one….not a Colt, Diemaco, or Armalite), a barrel (also the wrong one……20”HBAR instead of the 18” Douglas), Diemaco F/A BCG, Armalite Tactical two-stage trigger set (also the wrong specs, but who cares, no one will see it), and a KAC 600m USMC micro rear sight. I got the rear sight for dirt cheap, so I’m going to see if I can source a used front sight without having to pay full pop.

    Since One Shot Tactical helped me source the KAC M4QD flash suppressor for my Mk18 build, I hit them up for the KAC Free Float Rifle RAS which should be here in about 4-6 weeks. It’s $465 CAD plus tax and shipping for the cheese graters, which is a bit of a shocker for me because there are a lot newer, and probably lighter hand guard options now for far less. That being said, I know that KAC is top notch in quality, and I’m building another clone for no apparent good reason. Besides, I did a little snooping on US websites and found they list for about $350 USD which works out to about $467 CAD before tax, shipping and import fees. With that in mind, $465 from OSS doesn’t sound that bad. I also did a little scanning on Fleabay and noted that the KAC Free Float Rifle RAS is averaging about $600-700 USD right now and I have no idea why. People are going a little crazy on the bidding for some strange reason.

    I’ve also got one of those KAC stripped SR-15 lowers on pre-order so hopefully that will arrive around the same time as the hand guard.

    Quote Originally Posted by Troglodyte View Post
    I give you $200 for one of your kidneys to help you get start it.
    I may have pre-sold my kidneys to someone in Chinatown a while ago when I was building my Mk18. Friggin hell this hobby is expensive, lol!

    Quote Originally Posted by Yuri Orlov View Post
    Who are you trying to fool? You will go full retard on this one too. Wouldn't be right if it wasn't perfect.
    Lol, I’m already off track with the wrong length barrel (20” instead of 18”), so I think I’ll be okay this time. The only major concern with the Mod 1 build is the barrel sleeve and muzzle brake. That might be a bit tricky to find…..then after that, I have to worry about glass and mounts. I may end up finding something close enough on this as well, hahaha!
    “The greatest happiness is to scatter your enemy, to drive him before you, to see his cities reduced to ashes, to see those who love him shrouded in tears, and to gather into your bosom his wives and daughters.”

  6. #6
    Member
    Join Date
    Apr 2015
    Location
    Surrey, BC
    Posts
    325
    I am not an animal I am a human bean!

  7. #7
    Quote Originally Posted by Troglodyte View Post
    Yup, that's exactly what I was looking at!

    Some mod 0 love:











    I am highly intrigued by the complete uppers from PRI.











    $1,556 USD though...and that's before any shipping, tax and import fees (would probably have to go through irunguns or something to bring this in. $2,073.14 plus shipping/import fees/taxes is a hard pill to swallow, but I may actually do it one day, depending on how my tax return goes, haha!

    Will definitely have to have a chat with Aztec Armories to see what it will cost.
    Last edited by mister donut; 03-23-2017 at 04:03 AM.
    “The greatest happiness is to scatter your enemy, to drive him before you, to see his cities reduced to ashes, to see those who love him shrouded in tears, and to gather into your bosom his wives and daughters.”

  8. #8
    Well, it seems like I may have to check with Aztec for importing some other stuff as well. The OPS Inc brake and SPR collar aren't exactly cheap. There's another company called Allen Engineering that makes almost the exact same product I may have to look into:

    https://www.adcofirearms.com/acc/pro...gory=Silencers

    Yeah, this project isn't going to be easy, or cheap, lol!
    “The greatest happiness is to scatter your enemy, to drive him before you, to see his cities reduced to ashes, to see those who love him shrouded in tears, and to gather into your bosom his wives and daughters.”

  9. #9
    Member
    Join Date
    Apr 2015
    Location
    Surrey, BC
    Posts
    325
    Sourcing parts piecemeal is going to suck cost wise, I did some digging before Xmas, Brownells carries a few parts, but if the total adds up to over $500 that might require an export license which would be another $250.

    Here are some of the parts I found on Brownells.
    -PRI gas buster -$89.99
    -PRI folding front sight -$189.99
    -PRI 14" CF Gen 3 forearm -$403.00
    -PRI AR15 SPR straight top rail -$200

    That leaves the collar, brake, rear sight, BCG, upper receiver and more importantly the Douglas Barrel , it can easily add up to more than just getting the $1600 complete upper from PRI.
    I am not an animal I am a human bean!

  10. #10
    Yeah, I think for my my Mod 0 build, it won't be much of a build, I'll just get a complete upper.

    I'm afraid I've already started collecting parts for the Mod 1 upper, but it won't be a true clone because I'm already starting off with the wrong barrel, a 20" HBAR instead of an 18" Douglas, and aside from the differences in barrel length and profile, I'm not even sure the collar would fit the HBAR. Kind of kicking myself because apparently there's a company in the states called Centurion Arms that makes a Mod 1 upper for $1,350......$*#&@! Haha!

    Man, I really hope I do good on my taxes this year because I will probably splurge on a complete Mod 0 upper.
    “The greatest happiness is to scatter your enemy, to drive him before you, to see his cities reduced to ashes, to see those who love him shrouded in tears, and to gather into your bosom his wives and daughters.”

Page 1 of 7 123 ... LastLast

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •