The upper is a Mk12 Mod 1 clone on a Colt receiver with all parts being authentic (to my knowledge) except the barrel. if you like … RECCE Barrel. Barrel extension: M4 feed ramps. Specs. https://www.operationparts.com/centurion-arms-mk12-barrel-matte-stainless-18 i have let people burrow it twice and have had to have a new one built both times cuz the person didn't want to give it back. Manufacturer: Naval Surface Warfare Center - Crane Division Model: Mk12 Mod 0/1 SPR Caliber: 223 rem / 5.56x45mm NATO Barrel: Douglas Premium Air Gauged - SPR Profile Barrel Length: 18" (457mm) Twist: 1:7" Magazine: 20 or 30 Round Detachable Box (M16) Trigger: Knight Armament Corp. 1, Monty and I continued our discussion of the MK-12 SPR platform, and get to shooting. I went with a Noveske 3-groove specialty barrel based off the Mk12 profile (not Noveske's "SPR barrel") with a profile for the Ops Inc 12th model can. After all, the Mk12 made its way into the battlefield in 2001, so that is a long time ago, and there are better rifles and better barrels out there than the 18" SPR barrel. 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 … https://www.opticsplanet.com/centurion-arms-mk12-barrel-riffle.html SPR/A, SPR/B, Mod1. AR-15 8 Step Cycle of Operation: Locked Chamber Dwell Time. 08 May. In this continuation from Pt. Available in both 14.5" and 16.1" lengths. 17 Jul. These are produced with the same chamber as our Spec. A: The beauty of the MK12 is that it came from a very specific need…military operators needing a good precision weapon for something that was 5-600 yards and in. Built for reliability and accuracy. The SPR/A and SPR/B both used the KAC M4 Match FF RAS. Q: If there’s one thing the MK12 SPR has proven not to be…it’s a fad. We have shortlisted four barrels, with hardware and gray or black coating ready to go. Re: Douglas Mk12 Mod1 barrel? MK12 barrels with a slightly heavier profile. Two ARMS #22 Throwlever 30 mm steel rings are used to mount the dayscope. Finally finished this damn thing. If you want to build your Mk12 to be historically, correct, then we are your huckleberry. This experience combined with gun barrel quality steels, our stringent inspections at every process, and Criterion employees’ commitment to quality make a Criterion barrel the best choice for your next barrel. Latest News. 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 … Generally: Specific SPR barrel profile on a 7 twist Douglas turned blank of 18" or 16" for the H variant. Selective Fire Trigger Group (Early), Geissele SSA-E (Late) Stock: M16A1, A2 Fixed, … HCS has been taking great care of guys on this site, monty from centurion arms is a good friend of mine and i have one of his mk12 uppers. Specs: Material: 416R Stainless. centurion and HCS have great barrels, pretty sure they are both from same place. Took 3+ years to finish it out. Its more of the whole "system" spec to be mk12.