Brand new build…..short stroking?

[camoman]

Initially I thought you were short on gas, but now I think you could be outrunning the bolt catch. H2 will probably help, but you could just try the ST-T2 in it first.

I was thinking of swapping buffer’s before I order anything. Unfortunately the weather here is terrible today.

[markm]

Initially I thought you were short on gas, but now I think you could be outrunning the bolt catch. H2 will probably help, but you could just try the ST-T2 in it first.

Yep. Too much bolt speed is a possibility. I've had it happen in the past... decades ago before we knew about gas ports and buffer weights.

If the OP's gun feels snappy, an H2 could only be helpful.

[camoman]

Yep. Too much bolt speed is a possibility. I've had it happen in the past... decades ago before we knew about gas ports and buffer weights.

If the OP's gun feels snappy, an H2 could only be helpful.

It sounds like this is my next step.

[camoman]

Thanks everyone. I will swap out buffers and test when the weather allows.

[markm]

It sounds like this is my next step.

No guarantees that this is the issue, but no matter what, I'd be running an H2.