I had a partial case head separation using a 1.8oz buffer

[DeNinny]

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Would a light buffer potentially put extra strain on the case a bit early? It's a carbine gas system.

To me the buffer is not going to move until the bolt carrier moves. And the bolt carrier doesn't move until the gas hits it. And this doesn't happen until after the bullet is just past the gas port. This is well after it left the case. By that point, the pressure in the chamber is dissipating and past its peak.

So to me the buffer and buffer spring is not in play for this failure.