Short stroke

[liljonh30]

One of my A.R. pistols just started short stroking it will not load the next round I pulled the bolt out did the bolt failed change the gas rings and put it back together and it still does it if I swap the upper it runs flawlessly so I know it’s something with the bolt or the gas system anybody have any helpful input when I take the bolt out it stands up without falling down, I have a new gas tube and extractor set I can install it. Literally every time I fire it I have to manually charge it when I swap the upper with one of my other ones it ran fine.I’m considering just buying a brand new bolt and changing the gas tube..

 

[timbgtm]

Are there any marks on the gas ports? Not alighted up maybe. Or tube?

 

[timbgtm]

cmshoot should be able to diagnose this much better than most!

 

[liljonh30]

I can look ,maybe something moved a bit

 

[timbgtm]

I can look ,maybe something moved a bit

I'm thinking out of alignment or the buffer may be to lite, being a pistol. But there's others better at diagnosis than me.

 

[liljonh30]

I just broke it down the gas block set screws were loose I think what you were saying was right it might’ve been off a tiny bit hopefully see him shoot will chime in and I’m going to reset the gas block

 

[kc30121]

My pistol did the same thing this summer and when I pulled the hand guard off I noticed the gas system had come loose. Realigned and put blue lock tight on the set screws and it’s been find ever since.

 

[timbgtm]

I just broke it down the gas block set screws were loose I think what you were saying was right it might’ve been off a tiny bit hopefully see him shoot will chime in and I’m going to reset the gas block

Sounds like this could be the problem.

 

[liljonh30]

Yes the gas block was loose I have Loctite 312 and 222 I put a little 312 on the set screws and tighten them back up they were both loose

 

[Plinker66]

If your barrel isn’t dimpled it will likely happen again