BCM bcg is failing the stand up test

[Gary556]

Less than 1k rounds ago I bought and started using a Bcm bcg, recently while cleaning and tinkering I noticed my bcg wouldn't stand up with the extractor extended on its own weight. Or the "stand up test". So I emailed BCM and the sent me instructions to do their test, remove the cotter pin, firing pin and the cam pin, turn the bolt upside down and the assembly should not drop out under its own weight. It passed their test…

I have a couple other c158 BCGs that have 3-4k on them and they stand up just fine. Am I crazy for thinking Bcm possibly wrong here?

I haven't been having cycling issues, yet. I think the Tism' is really getting me on this one.

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[Vernonia MW]

Are you experiencing problems with cycling?

 

[Gary556]

Are you experiencing problems with cycling?

Negative.

I'm just bugging about it because all the other surface research I'm doing says the rings are bad. Which isn't the end of the world, but when you spend the amount of money on a brand that's supposed to be good to go, I ocd on the little details.

 

[Towhead]

Your rings are not bad after 1k rounds. Did you know
its possible for your BCG to work without rings? And
believe it or not, "staggering" your rings makes no difference.

Use your BCG until something breaks.

 

[msgriff]

The test that BCM describes is the correct test. There are a number of incorrect test methods posted on the internet. Your image is from the TM 9-1005-319-23&P Army Technical Manual published by the Department of Defense.

 

[Gary556]

Your rings are not bad after 1k rounds. Did you know
its possible for your BCG to work without rings? And
believe it or not, "staggering" your rings makes no difference.

Use your BCG until something breaks.

I get it possible but I'm not the type to run it like that.

Oh it's getting used, doesn't mean I'm not asking questions though. With all the gun tuber and forum experts it's hard to know who and what is right.

 

[Gary556]

The test that BCM describes is the correct test. There are a number of incorrect test methods posted on the internet. Your image is from the TM 9-1005-319-23&P Army Technical Manual published by the Department of Defense.

Thank you.

 

[lucusloc]

The AR action is remarkably robust against mis-tuning. If you are not having an issue with cycling or notice unusual amounts of fouling buildup I would say you do not have a problem with your bolt. The difference between a BCG standing up on its own and the bolt not falling out under gravity is pretty trivial. Those rings are still sealing, they are just a tad bit loser than they could be (and let us not forget that rings that a too tight can be a problem as well). This very much seems to be a case of "don't sweat the small stuff."

 

[Tony617]

I have some replacement gas rings just in case I need to replace them at some point. I also have spare firing pins, spring kits etc. as well.

 

[Steel Head]

After a 1000 rounds I bet most has rings are a bit loose.
Run it till failure and have spares at hand.