Adam Arms piston kit failure

[CJ]

So, I decided to run some rounds through the 7.5" .223 SBR upper. I inserted a 20 round magazine, and on the 19th round it jammed and I couldn't remove the charging handle. Once I finally pried it open, this is what I found.







I spent quite a bit of time looking over the failure trying to figure out what happened. My gas block was tight against the barrel, it had not walked or moved in any direction. I checked it before hand and spent quite a while making sure it was aligned perfectly. The op rod contacted the middle center of the bolt, then it began to bend/walk up the bolt carrier until it bent over the top and jammed the rifle. Both the bolt and the op rod are ruined. I will have to cut the op rod in half to remove it.

I did some google searching and I found several people that have had the same problem, some attribute it to not having the gas block aligned, and some to not have it seated all the way. I definitely did not have these issues so I'm lost. That's 19 rounds. I'll talk to AA about it tomorrow.

[bigmuskie]

I was thinking you could just replace the gas key, but I expanded the pic and it looks like the carrier and key are one. If that's the case, sorry to hear that dude.

[KBScobravert]

I think it has to do with the pistol length rod. The longer rod might be long enough to deflect any side pressure that would otherwise bend.

[CJ]

I think it has to do with the pistol length rod. The longer rod might be long enough to deflect any side pressure that would otherwise bend.

It seems the overwhelming majority of people with problems have pistol length rods. At first I thought it was overpressured, but it was throwing brass to my right, not forward. I didn't feel any excessive recoil or anything out of the ordinary.

[LANTIRN]

I have a carbine length rod on mine; my cousin has two rifles with carbine lengths. The only issues either of us have had is I did not have my gas block aligned good and it would not cycle, but no damage. Got that corrected and neither of us have had any problems and all three guns have had a few thousand rounds through them at least. Adams Arms carbine and rifle gas systems have a ton of satisfied customers, but I did zero research on the pistol gas systems so I really can't offer you any good information other than I have used some of their products successfully.

I am interested to hear what they say after you talk to them as I had planned on using more of their products in the future. Please keep us updated with their quality of customer service; I had planned on buying one of their complete carbine length uppers in the future so I would love to hear some firsthand customer service experience.

[soap]

Ouch

[YALE]

Ah, shit. Sorry man.

[soap]

I'd send it back in pieces to show em.

[ThreeFingerPete]

That's rough man. Hopefully they're receptive and helpful.

[03trubluGT]

That's Eugene Stoner's way of payback for screwing with his design.

[Fatass]

That's Eugene Stoner's way of payback for screwing with his design.

I've kind of wondered the advantage of going to a piston system... I haven't had any issues with DI.

[Sleeper]

Piston is the way to go if its got a can for sure.

[Trick Pony]

I've kind of wondered the advantage of going to a piston system... I haven't had any issues with DI.

ARs run cleaner and cooler with a piston system since it's not directing all the hot gasses and crap back into the action. Once the piston has moved a short distance the gasses are expelled through a vent in the piston tube.
This usually translates to a more reliable rifle too, but I guess CJ's gun proved otherwise with a pistol length gas system.
I'm curious if the manufacturer will blame this on improper assembly or some part other than the piston setup. I know CJ knows his shit so I believe him if he says it was put together right.

[CJ]

Piston is the way to go if its got a can for sure.

That's the reason I decided on it, if you think DI is dirty, just try it with a suppressor forcing twice the particulate back into your action.

ARs run cleaner and cooler with a piston system since it's not directing all the hot gasses and crap back into the action. Once the piston has moved a short distance the gasses are expelled through a vent in the piston tube.
This usually translates to a more reliable rifle too, but I guess CJ's gun proved otherwise with a pistol length gas system.
I'm curious if the manufacturer will blame this on improper assembly or some part other than the piston setup. I know CJ knows his shit so I believe him if he says it was put together right.

I certainly followed the directions the kit has. I made sure the gas block was aligned vertically over the gas port, I aligned the barrel nut and delta rings, inserted the stainless bushing, made sure the op rod did not contact the bolt when it was locked in battery, and used a feeler gauge to verify 0.020" of play at the plunger/block. The op rod moved freely without the spring. So, my only guess is it's either something not covered in the instructions, or some sort of problem with the kit.

[Sleeper]

I just hate shooting a di with a can.

By the time your done shooting your face looks like a coal miner.