I have a PSA upper that I purchased specifically because it had the correct specs for an SPR build (1/8 twist 18” barrel with a rifle-length gas system), along with the bonus of being chambered in 223 Wylde. Since then, I have fallen in love with the Mk12 Mod 0, and have already started to accumulate the parts to convert the upper to this look.
Someone has advised me that the Ops Inc. muzzle brake collar so integral to the Mod 0 look may not be properly staked to a non “SPR-contour” barrel. Is there any way to tell if my barrel has this contour, or if not, are there any solutions short of replacing the barrel? I’m very happy with the accuracy and of the FN barrel and would rather keep it if possible.
A proprietary blend of Hammer forged chrome molly vanadium made by FN that is referred to as "Machine Gun Steel" by virtue of its use in FN's M249 and M240 weapons. The hammer forging process work hardens the steel, making it more durable. In addition, the chrome process for the bore allows for a lining almost twice as thick as a standard M16 for enhanced durability. Chambered in 223 Wylde, with a 1/8 twist, M4 barrel extension, and a rifle-length gas system. Barrel is High Pressure tested, and Magnetic Particle inspected, to ensure quality and dependability, and is finished off with a Midwest Industries SSK 15" rail, low profile gas block and A2 flash hider."
PSA 18" CHF 223 Wylde 1:8 Rifle Gas