What happened to this fired 28 Nosler brass??

[M5NSX]

Brass from my suppressed 28 Nosler Cadence bolt gun. Four out of the 20 I fired came out like this. Velocities on all the rounds fired in the 2860’s fps. These have been loaded 3 times-195gr Bergers with 77.8gr of Retumbo and CCI 250 primers. The other 16 fired pieces were fine. What’s going on here? Thanks

 

[Supersubes]

Brass isnt sealing the chamber. Work hardened brass and/or too little chamber pressure.

 

[M5NSX]

Brass isnt sealing the chamber. Work hardened brass and/or too little chamber pressure.

I loaded these when I first got into reloading. Made some errors ie not sized properly but I fixed all that. I did not have my amp annealer at that time so I know for sure they were not annealed when I loaded them. Don’t know if the previous owner annealed them. I‘m assuming annealing them would prevent the brass from hardening? None of my 338LM, 300NM or 300WM loads have done this.

 

[Supersubes]

I loaded these when I first got into reloading. Made some errors ie not sized properly but I fixed all that. I did not have my amp annealer at that time so I know for sure they were not annealed when I loaded them. Don’t know if the previous owner annealed them. I‘m assuming annealing them would prevent the brass from hardening? None of my 338LM, 300NM or 300WM loads have done this.

The rate at which they harden is a function of chamber and die size. Proper annealing will prevent that from happening.


How many times did the previous owner fire them? Id personally never consider using unknown history used brass. Its a needless variable.

 

[jakelly]

You need to put more powder in the case.