Colt Piston Carbine 18” 5.56 Precision Reflex PRI Mk12 SPR Upper AR15 Rifle
SOLD FOR: $1,625.00
LSB#: WY250421ML023
Make: Colt
Model: Piston Carbine lower built out to be a MK12 SPR
Serial Number: LP003049
Year of Manufacture: Modern
Caliber: 5.56
Action Type: Semi-Auto, Direct Impingement, detachable magazine fed. This rifle has a California compliant lower that requires the upper and lower be separated before the magazine can be released. This rifle has the Kingpin quick release rear takedown pin.
Markings: The left side of the receiver is marked “COLT / PISTON CARBINE TM / CAL. 5.56MM. / LP003049”, “COLT DEFENSE / HARTFORD. CONN. / U.S.A.”, “SAFE FIRE”. The upper receiver is marked “Precisionreflex.com”. The barrel is marked “5.56 1/8D”.
Barrel Length: 18” medium profile barrel 19.5” with Allen collar and muzzle device for mounting an AEM5 suppressor.
Sights / Optics: The rifle has a 17.5 inch picatinny rail for the mounting of optics and accessories. There is a flip up hooded Iron sight integrated into the gas block and a flip up dual aperture rear sight integrated into the top rail.
Stock Configuration & Condition: The furniture set on this rifle includes an A2 style butt stock with a 13” length of pull, and storage in the butt, an A2 pistol grip, and the 12.5” PRI tube MK12 SPR forend with mounted picatinny rails for mounting accessories. Currently mounted is a Harris bi-pod with an ARMS QD mount adapter and a Knight’s QD cup. The furniture shows some minor handling wear mainly on the stock. None of the marks are notable. Overall the furniture is in Very Good+ to Excellent condition.
Magazine Quantity & Condition: This rifle includes one x 10 round Colt metal magazine in Very Good+ condition.
Type of Finish: Black
Finish Originality: Original
Bore Condition: The bore is bright and the rifling is sharp. There is no erosion in the bore. The feed ramps are smooth and shiny. The muzzle is clean. In this writer’s opinion the bore rates 10/10.
Overall Condition: This rifle retains about 99% of its metal finish. The rifle shows minor scattered marks from handling and transport with none being notable. The markings are clear, the screw heads are sharp, and the pins clean. Overall this rifle is in Very Good+ to Excellent condition.
Mechanics: The action functions correctly. This rifle has a California compliant lower that requires the upper and lower be separated before the magazine can be released. We did not fire this rifle. As with all used firearms, a thorough cleaning may be necessary to meet your maintenance requirements.
Box, Paperwork & Accessories: This rifle includes a harris bi-pod with a ARMS QD mount, Colt magazine, and QD sling adapter.
Our Assessment: This rifle is a faithful MK12 SPR-style build utilizing a Colt California-compliant lower originally designed for a piston-driven carbine but now paired with a direct impingement PRI MK12 upper. The lower features a Kingpin system, which locks the magazine in place and requires upper-lower separation for reloading, satisfying California’s fixed magazine laws. Classic A2 stock and grip components maintain the traditional handling characteristics, while a Geissele trigger refines the fire control group for crisp, precise breaks suited for long-range shooting.
The upper is a proper PRI MK12 configuration, complete with the signature carbon fiber forend and integrated flip-up iron sights. The 18″ barrel is outfitted with an Allen Engineering collar and muzzle brake, making it compatible with the AEM5 suppressor system. This build mirrors the original SPR concept, precision fire from a light, semi-automatic platform, and includes a PRI charging handle and Harris bipod mounted via an ARMS QD adapter. Despite being built on a lower originally made for a piston gun, this rifle maintains the true direct impingement operation of all authentic MK12 platforms. Please see our high quality photos via the link and best of luck with your bidding!!!-R.L.
