Loose gas key

[nightchief]

I would be worried that one of the bolts is broken. The staking holds the top in place, but it's separated from the part in the carrier.

Bolts appear to be in tact...

Attached are pix of the bolts and the key...

Attachment 35211

[nightchief]

looks like the pic of the bolts didn't attach...trying again

Attachment 35212

[MistWolf]

Replacing the screws is cheap insurance. Shooting the AR with the gas key screws loose will cause the screws to shear. The old screws may already be damaged

[nightchief]

Agree...I will be getting new bolts and a new gas key for it.

Replacing the screws is cheap insurance. Shooting the AR with the gas key screws loose will cause the screws to shear. The old screws may already be damaged

[HansTheHobbit]

The screws don't actually have to move for the gas key to come loose. Once that seal between the gas key and carrier is compromised, the pressure will cause the threads to stretch. That's why some people don't believe in staking, as it doesn't seem to prevent much of anything. So long as the screws are torqued down hard enough, they're not going to spontaneously rotate on their own.

The most important part of installing a gas key is preparing the surfaces. You can stake those screws as hard as you want, but it won't do a thing for you if you didn't get a good seal to begin with.

[mark5pt56]

I would be worried that one of the bolts is broken. The staking holds the top in place, but it's separated from the part in the carrier.

That happened to me, able to get the other one off and enough screw body for pliers. New screws and stake, good to go.

[lysander]

How do I stake the gas key? I mean, what tool(s) is/are used for this? I've staked endplates, but never a gas key...

NC

Get out your copy of TM 9-1005-319-23 and P (here)

Go to Work Package (WP) 0013, it deals with the entire process of replacing the carrier key, staking is specifically addressed on page 0013-2.

[Artiz]

The screws don't actually have to move for the gas key to come loose. Once that seal between the gas key and carrier is compromised, the pressure will cause the threads to stretch. That's why some people don't believe in staking, as it doesn't seem to prevent much of anything. So long as the screws are torqued down hard enough, they're not going to spontaneously rotate on their own.

The most important part of installing a gas key is preparing the surfaces. You can stake those screws as hard as you want, but it won't do a thing for you if you didn't get a good seal to begin with.

The vast majority of gas keys vent out gas from under the gas key. Unless some gasket sealing compound was used, which is opposite to the "mil-spec", it's gonna vent gas.

[Iraqgunz]

Staking is only debated by sub par companies that don't do it. I have seen very few stakings that were done correctly result in the key coming loose.

Knowing BCM customer service, they'll probably fix it. If not, then just crank 'em back down. It's actually up for debate whether staking does much good or not. It certainly doesn't hurt, except that it's permanent, but as you have experienced it's entirely possible for even properly staked gas keys to come loose.

[nightchief]

I contacted BCM and they requested I send it back to them to evaluate. Will follow up when after BCM evaluates the carrier and key.

NC