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

[LRRPF52]

That is a hot, compressed load.

QL is predicting your load is 64K lbs (Grendel SAAMI is 52K lbs). 106% case full is crunching powder when you seat the bullet. Pressures increase exponentially when powders are being compressed, and also less predictable as you change the burn characteristics. 2520 is a bulky, slow powder for Grendel out of a short barrel. The case becomes full before the powder becomes compressed.

I'd be loading no more than 27.8 which is exactly 100% full and right on the SAAMI pressure limit for 2520.

What does the case look like?

QL told you that this load would generate 64,000psi. That’s 12,000-14,000psi more than all of the available actual pressure test data from calibrated 6.5 Grendel test breeches.

Do you at least understand why I say QuickLoad isn’t a valid tool here?

I’m literally looking at all of the available pressure test data with multiple 123gr bullets, most of which have more case intrusion than the 123gr ELD-M, similar jacket thicknesses and hardnesses.



If you’re comfortable with a program that kicks out those kinds of numbers, it really defies the general attention-to-detail I’ve come to expect from your posts.

I don’t know what the issue is with fixation with QL. It’s just wrong with the numbers it generates for 6.5 Grendel, by huge margins.

This is the reasoning behind why I call out QL the way I do. It isn’t a personal slight on anyone if they happen to be involved with it professionally.