Peterson vs Starline brass (weight vs capacity) 6 Creedmoor

[js2013]

The Peterson LRP is 5 grains heavier than the Starline SRP, yet case capacity was about the same. This was with once fired brass. Sample of 1.

I’m guessing Peterson has more brass at the base. Perhaps this explains why some folks get longer brass life with Peterson.

 

[Straightshooter1]

The Peterson LRP is 5 grains heavier than the Starline SRP, yet case capacity was about the same. This was with once fired brass. Sample of 1.

I’m guessing Peterson has more brass at the base. Perhaps this explains why some folks get longer brass life with Peterson.

I think you have to take the case wall thickness into account too, as it's not just about the web thickness. Also, there can be substantial differences from one lot of brass to another, so one can't really make a hard assumption that such a difference is going to always be so.

Here's some numbers regarding my .308 cases along with numbers published by Peterson: