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

[LRRPF52]

There's nothing I've said that's a contradiction.

And I have fully evaluated and understand the buffer mass and cyclic rate physics.

And I fully understand the system of an AR firing a bullet from beginning to end. The overall complexity of it is minor in my professional opinion because of many more complex engineering "problems" that I've faced in school and my career. It literally and figuratively isn't rocket science to me.

A lack of fully understanding the materials science properties of metals and alloys and the entire math behind their deformation at temporary, permanent, and absolute failure phases has led to a series of conjectures and contradictions that simply do not match up with what the OP has posted, and I’ve had to waste a lot of time addressing these falsehoods in this thread.

If you aren’t completely proficient at the math behind materials science as described above it isn’t helpful positing all kinds of theories in a thread where the OP came looking for help.

Chuckles in Aerospace Engineering. I put myself through the NATO/West German AeroE course from 1986-1989, repeatedly referencing and studying that coursework from pure intellectual curiosity and a passion for aviation that I, my family members, and neighbors were all involved with in military developmental aerospace communities.

The materials science, gas dynamics behavior, and mechanical engineering involved in the AR-15 or any other firearm are child’s play compared to the AeroE sciences, but I take them very seriously and perceive them coming from that space. There are other things I have done specific to this I will keep close to the vest, but funded technical analysis of US and foreign weapons has been something my family and I have been involved with for decades. Just in the private sector alone, I have been involved with final QC and design input on production rifles, in addition to Total Quality Management training from the business end.

More importantly though, I’ve been a student of this particular firearms design prior to that, first gaining hands-on with it in 1987 and have never let go of it since that time.

The first 20 years of intense study, deployments, builds, troubleshooting, and researching the better historical accounts of it was the "climbing the mountain" phase.

Not until I really dove back into the 1959-1967 designs looking at it from a reloading perspective, did things start to finally make much more sense.

Getting into 6.5 Grendel in the 2000s expanded that understanding much further, because you learn to see what things you took for granted before.

A Chemical Engineering or structural engineering degree isn’t much help in that regard, especially if it leads you to false conclusions that ignore some of the basic tenets of metallic cartridge behavior and pressure-containment systems and their specific failure nodes. Basic engineering principles are absolutely essential, but you really need more extensive training and experience in the field to correctly diagnose catastrophic malfunctions. Why were so many false conclusions jumped to early-on in this thread by supposed school-trained engineers?

A false sense of intellectual acumen with limited applied knowledge in the field can then lead to really bad initial assumptions, which are then doubled-down on-as has happened in this thread, with patently-absurb conclusions about Lapua brass being suspect, unsupported phenomena of case head failures, and refusal to see the obvious.

I’ve seen other engineers who have made multiple errors and assumptions about pressure containment, because they came from a structural engineering background without formal or long-term experience in firearms engineering, but still decided to get into firearms. The basics apply, but there still is a mountain to learn.

In this case, ego allowed posters in this thread to derail it instead of waiting for us to get all the relevant data before the culprit became obvious.

Instead of accepting that, there is now an expectation of appeal to authority fallacy where there is no authority.

Any salty ME with decades of firearms experience will look at this and agree that the extremely lightweight 1.8oz buffer, combined with CLGS allowed for early unlocking to occur.

Literally all of the evidence we have seen points directly to that.