Never heard that. Never seen that either. I have seen plenty of loose primer pockets in ADG brass run warm.
I know that Alpha brass has their "OCD" brass (Optimal Case Design w. Optimized Case Head Technology) and is thicker brass throughout the entire case, leading to less case volume and increased pressure with similar charge weights used in other brass.
I have used Hornady and ADG, and have some Lapua to try next. ADG is leaps and bounds better than Hornady. I am looking forward to testing the new Lapua brass this weekend.
The increased speed in ADG has nothing to do with alloy of the metal, it's the smaller capacity and running higher pressures. It is tougher and would tend to show pressure later than others.
If Alpha had PRC brass I would run it.
The general consensus seems to be that:
ADG is harder, thicker and smaller capacity which is why it hits speed faster. Also highest cost. Excellent quality
Peterson is softer, thicker (also smaller capacity). less $ than ADG and even a little less than Lapua. Excellent quality
Lapua is well, Lapua. It's pretty much the standard to judge by. Lapua is a less $ than ADG, slightly more than Peterson and a lot more than Hornady. a little bigger capacity than ADG & Peterson. I have seen capacities listed similar to Hornady or maybe slightly less. Excellent quality
Hornady is least tough, biggest capacity or or possibly same/similar to Lapua capacity. Lowest case life, most prep and variability and lowest cost. It is decent/good quality but not up to the others standard.
I have Lapua inbound for the 300 PRC I am building and also some on hand for a 6.5 PRC. I have a box of Hornady 300 PRC here so I'll compare that to the Lapua and see. I only have first hand of the Lapua and Hornady.
I have Lapua for several other rifles. I am selling the new stuff I got for my 6.5 CM as I want to try out the Alpha on a new barrel when I finally get that from Bartlein.
Not sure if that helps or not.
