The measurement I gave in my previous post was the average of 20 fired cases.
Post # 19 explains the measurements in more detail & shows me that the cases are within SAAMI spec.
I thank you for the additional info. The commentary puts everything into the proper perspective......
No problem, been to Trops many, many times. Was your 30-30 new or used and what year did you buy it.
Below two of my rimmed favorites, the 30-30 is the trapper model with a 16 1/2 inch barrel.

And below my 30-30 cases never do this at 42,000 psi, but at 49,000 psi the .303 British case will stretch and have case head separations.

Last edited: