AR trouble at the range......

[blacklabelmongo]

You mean were supposed to clean them? =x

 

[Fyrtwuck]

The only thing I can think of is that it is a gas problem. When I built my SBR I had to play with different weight buffers to get it to run right.

 

[SMS]

The bolt is cycling. I was able to fire the first round no problem then it would get hung on the second round. It soon after that quit ejecting the first round as well.

So it's cycling, as in the bolt is travelling to the rear (at least partially) after the shot, yet leaving the spent case in the chamber? Or are you getting a 'bang' with no corresponding bolt travel to the rear at all, with bolt still locked forward and the extractor engaged over the case?

How does your extractor look? Did you build your bolt with a new spring and spring buffer?

 

[kevin40_2001]

So it's cycling, as in the bolt is travelling to the rear (at least partially) after the shot, yet leaving the spent case in the chamber? Or are you getting a 'bang' with no corresponding bolt travel to the rear at all, with bolt still locked forward and the extractor engaged over the case?

How does your extractor look? Did you build your bolt with a new spring and spring buffer?

Correct! I am getting a bang but the bolt was still locked forward. I looked at the extractor while cleaning and it appeared fine but did have a lot of grime as well. I built this SBR will all new parts. It has ran perfectly with no problems for almost a year now.

 

[SMS]

Dang...after checking the key and rings (they don't have to staggered), trying different ammo and mags, and giving the chamber a good scrubbing the only thing I could think of at this point is the gas port/block alignment. Any sign of blow-out or a large amount of leakage around the front site/gas block?

Doubt it's the recoil buffer and spring...even with a poorly matched combination you should get some bolt travel.

 

[Zombie]

sounds like no gas/clogged gas system or something there for sure. I'd be willing to bet it's either the gas system dirty/clogged up or the gas block out of alignment.

 

[dieseltech09]

I had a friend put an AR together and left out the pin on the gas block end of the tube. The tube would rotate and he would have this same issue.

 

[madbrad1953]

I would first try differnt ammo alswats start trouble shooting a propblem with the simplest thing to do first, did youy check the gas rings on bolt to insure they are all 3 staggard and not lined up if so that will allow too much gas to blow by and cause the gun not to cycle

 

[SMS]

did youy check the gas rings on bolt to insure they are all 3 staggard and not lined up if so that will allow too much gas to blow by and cause the gun not to cycle

Sorry, but that is urban legend...or should I say old school weapons instructor B.S.. You can line them up and the weapon will work fine, providing nothing else is messed up.

In fact, try lining them up and spend some time shooting...when you are done, you can strip the bolt and discover that they aren't lined up anymore. They slowly rotate with every cycle of the BCG.

 

[Norman]

If it were me, I'd put another bcg in there, then see if it will run. If it doesn't, I'd buy a new gas tube, remove the gas block, install the new gas tube and then see if it'll run. Replacing the gas tube isn't really necessary, but it sounds like you're having a gas issue and replacing the tube would make me feel better. Regardless, I'd try a new bcg, then reinstall the gas block.