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

[LRRPF52]

You realize that is a screenshot of quickload? Regardless it is exactly the demonstration I was speaking of. I did miss the reduced buffer weight.

Yup. I’ve been looking at screenshots of QL like that for illustrating peak and residual pressures for well over a decade.

Both things are true. QL is totally off the mark (by thousands of PSI) on its predicted chamber pressures in 6.5 Grendel.

Barrel length pressure curve models like this are great illustrations of how pressure subsides as volume increases in the containment vessel.