Ruben Nasser
New member
I have a Colt AR15 16" pre ban carbine, 1 in 9" barrel with an aftermarket muzzle brake. It jams with military ammo (full power 55 FMJ), Win or Korean good stuff that shoot beautifully in my friend's AR15s. This does not happen with other ammo (heavier bullets or reduced velocity). Seems like the typical stoppages of the early AR15 era accounts, because of too much gas pressure too early. The extractor just slips over the rim of the case or breaks it, leaving a stuck case in the chamber. Chamber is not rough, everything is new, clean, and in (apparently) excellent condition in the rifle, and I have exchanged with my friend's bolt, recoil spring and buffer, and it keeps on jamming. The last part I have to isolate is the gas system, could it be out of spec? How can I check it? Maybe the gas entrance drilled in the barrel is oversize? Can the muzzle brake be a cause? (I'm going to try without it, anyway). Any ideas wellcome!! Thanks!!
[This message has been edited by Ruben Nasser (edited July 10, 2000).]
[This message has been edited by Ruben Nasser (edited July 10, 2000).]