Hi all,

I recently completed my first AR build last week and took it out to the mountains this weekend for a test run. I ran into an issue where a round would get stuck in the chamber. It would be shooting normally then  after a few rounds, I would pull the trigger and would get a FTF. I try to pull back the charging handle but it's stuck - I end up getting it open by holding the latch open and pounding down against the CH. 0I examine the round and the casing is scratched up and dented in places.

I suspected the ammo (reloads) was bad so I tried some factory Remingtom ammo in my rifle. It worked flawlessly.

I then tried the remaining "bad" ammo (about 15 rounds) in the mag. I stuck the mag in a buddy's AR and they all fired flawlessly.

I have a new USGI mag (Labelle) that would not drop free when I push the mag release (other mags seem to work just fine). This same mag drops free in my buddy's rifle. It looks like this only happens in my AR, so I suspect there is a little tightness in my lower's magwell. My lower is a RRA which I purchased brand new in these forums.

Has anybody ran into something like this? Do I have to file something down inside my lower? Any help/advice would be appreciated.

TIA,
Derek

May be the reloads. I had a rifle give me the a similar  problem with some foreign ammo a few weeks ago. What was happening to me was the cases were a little long to fit in my chamber. The bolt would start to lock in but since it was not fully locked the firng pin would not hit the primer. I had to pry the carrier back with a screw driver to get it to open back up. The round had the bolt held in tight. I have not tried the ammo in a gun with a little more headspace but I suspect it will fire ok. You could get a gunsmith to check your rifle for correct headspace.

Tweak,

I am in the Seattle area.

Derek

Not fully ejecting or not loading 2nd round is Short Stroking comon on a new weapon until it breaks in. It took mine around 100 rounds, now she is flinging them.

UMC works fine for me. Only ones that have problems with not are WOLF do not load 2nd round and S & B does this every so often like a couple per box.

Also see Mystified ?? post

Thanks for the offer, Tweak. Let us know when you set up shop.

It looks like things are now OK. Last night, I installed a few parts that came in the mail - A Magpul enhanced trigger guard, reduced power trigger/hammer spring set, and KNS anti-walk pins. Before I proceeded, I sanded down a tiny imperfection at the rear of the magwell.

I put everything together and did a full function check. I stuck the "problem mag" in and hit the mag release - it now drops free. Not sure if my sanding the magwell helped, but the rifle seems A-OK now. I'll take it out to the range tomorrow and find out for sure.

Thanks,
Derek