AR FTF Issue

[RMC5]

I'm having a lot of issues with my dad's upper failing to feed the next round. It generally ejects the spent casing but sometimes doesn't. I'm thinking its the BCG not coming back far enough to pick up the next round but not sure. Can anyone point me in the right direction of what could be causing it or someone who could give it a look. I'm located in the IE. Thanks in advance.

[Saym14]

1 ) It generally ejects the spent casing but sometimes doesn't.


2) BCG not coming back far enough to pick up the next round but not sure. .

clarify the problem. you need to provide a better description of what happens. in 1) you describe a fail to extract or is it eject ? 2) sounds like a fail to feed.

[RMC5]

It's always a failure to feed and sometimes a failure to extract. the bolt is coming back forward without the next round.

[falbuff]

Try a different mag.

[RMC5]

I've tried 5 different types of mags, and swapped out the buffer and spring.

[uxo2]

What ammo..
And build info.
Pics would be nice of your upper and BCG.

[a308garand]

It's always a failure to feed and sometimes a failure to extract. the bolt is coming back forward without the next round.

Bolt not coming back in recoil far enough to feed fresh round off of magazine:

Underpowered ammo:
-What ammo are you using? Is it weak Wolf brand or known good quality stuff?
-Is the chamber cleaned with a chamber brush and solvent?
-Parts well lubricated with oil?

Check the rifle for gas leaks:
-gas rings in good shape?
-gas key staked in place and tight to bolt carrier?
-gas gey screws tight and not broken?
-gas tube not dented or broken?
-gas tube retaining pin missing from front sight base?

Check the recoil spring:
-If the rifle has a carbine length receiver extension...is the spring too long (like the length of a rifle spring)...should be around 10 1/16" min- 11 1/4" max. Rifle length is longer, 11 3/4" min- 13 1/2" max.
-Check the buffer to ensure you have the right parts. Carbine buffer and spring in carbine length...Rifle buffer and spring in rifle...the parts do not mix.

Some of the things to look at, its hard to pin it down with limited information...

[RMC5]

Federal 223, Herters 223, and LAX 5.56 reloads. It's a POS AR depot upper that I urged him not to buy. He's since purchased a PSA upper but would still like to get it going.

[RMC5]

I'm leaning towards it being a gas issue.

[6mmintl]

vented buttstock screw?

[atdski07]

Gas problem

[RMC5]

Thanks, so get an armorers wrench, take it apart and rebuild it while checking everything?

[Eric B]

This may sound ridiculous, but how's that gas key?

Tonight I fired my new build and after four rounds it was having the same issue as yours. I was already suspicious of a ****ty staking job on the gas key bolts so I looked there first. Sure enough, they were loose. Cranked'em down and all was well with the world

[RMC5]

This may sound ridiculous, but how's that gas key?

Tonight I fired my new build and after four rounds it was having the same issue as yours. I was already suspicious of a ****ty staking job on the gas key bolts so I looked there first. Sure enough, they were loose. Cranked'em down and all was well with the world

You were exactly right. Tightened them up and it ran like a champ. Thanks!