Ar problem

[leemozoid]

No, I meant is the fact that it has the Magpul equipment. Is that the reason that this 6920 lower was staked and the OP's wasn't. I usually build my own but after I picked up a 6921 upper I got a Colt lower to mount it on.

 

[uncle money bags]

No, I meant is the fact that it has the Magpul equipment. Is that the reason that this 6920 lower was staked and the OP's wasn't. I usually build my own but after I picked up a 6921 upper I got a Colt lower to mount it on.

Understood.
The magpul equip has nothing to do with it. They should leave the factory staked regardless. If they dont then at least two departments screwed up, the guy who was supposed to stake the end plate and the guy who was supposed to check it before packaging.
I have heard anecdotal evidence that this has occurred in the past with colt so i dont dismiss the op out of hand. However, i am suspect of a second hand gun which had been modified by the original owner. I have never seen a factory colt gun that was not staked properly.

 

[Shootin 4 Fun]

Went shooting last weekend the gun jammed again. Had to bring it home remove the buffer tube and tap the bolt in with a rubber mallet to fully seat the round then had to pull the charging handle back like a mofo to get the round to eject. The I ran about 80 rounds through it pulling the charging handle and a few of the bullets had caught on the feed ramp and nicked a chunk out of the tip of the bullet. Any idea on what would be causing this. Only happened with the reloads none of the store bought stuff did it.

The reloads are loaded too long.

 

[Cmcmill]

That's what I was thinking just wanted to run it by some people with more experience.

 

[Keelty]

The reloads are loaded too long.

You sure know a lot about AR15's

 

[uncle money bags]

The reloads are loaded too long.

Are you talking overall length or case length s4f? It sounds more like a sizing issue to me.
More specifically, like the cases were not properly full length resized and are too large at the web. This would explain why they seat partially and then become stuck. The same thing could happen if the brass is not trimmed to length, but those dont seem to be as hard to extract as the op says. Also, the hanging up on the feed ramp could be because the previous round was so difficult to extract that the momentum of the bcg was retarded to point of not being able to fully strip the next round from the mag.

For the op,you should never need to force around into the chamber with a hammer! If the round is that difficult, something is very wrong and you should stop and fix it.
Op, do you have any pics or measurements of the reloads that did not chamber correctly?

I think it would be well worth your time to take a short road trip over to FBT with the rifle and ammo for them to look at. I promise you will learn alot from the experience.

 

[Cmcmill]

Yeah I'll post some pics here later today. I've been meaning to take it over to fbt just haven't had time yet.

 

[dennishoddy]

Also, the hanging up on the feed ramp could be because the previous round was so difficult to extract that the momentum of the bcg was retarded to point of not being able to fully strip the next round from the mag.

For the op,you should never need to force around into the chamber with a hammer! If the round is that difficult, something is very wrong and you should stop and fix it.
Op, do you have any pics or measurements of the reloads that did not chamber correctly?
.

This^^^^ Give your sizing die another 1/8 of a turn, and your sticky round problem will likely go away

 

[Cmcmill]

I checked some in some calipers and there is quite a difference in length. I'll post some pics in a few is there a standard length for 5.56 rounds?

 

[uncle money bags]

I checked some in some calipers and there is quite a difference in length. I'll post some pics in a few is there a standard length for 5.56 rounds?

The book will probably say 2.20 to 2.26 inches overall depending on the bullet. The fact is if you can fit them in the magazine, then the length is not an issue. In fact, some long range, bench rest guys actually load longer than mag length and feed them one at a time without a magazine.