300 win mag H1000 load

[KYregular]

Just tested a load I worked up with some new Peterson brass. As follows
300 WM 26" barrel Weatherby Vanguard II
200 grain Accubond
76.5 grains H1000
Federal GM215M primers
3.526 OAL.
2.893 Ogive measure (.030 off lands)
88 degrees
Velocity avg 2910
SD 6
1" groups off bags

I had a load using RP brass with 78.5 with similar results, but I've been told Peterson was thicker brass some I loaded down, with good reason now. Light ejector marks on case, and small cratering. I'd like opinions on the brass in the pic provided, and be careful if you load this brass because of capacity. Also, bolt lift seemed smooth with no force needed.

 

[Blue68f100]

The ejector makes concern me, but the primers show no indications. Fed primers are normally a little softer than most. I haven't seen H1000 around here long before the craziness started. I don't know if the Peterson brass is soft, or not. May remove a few primers and see if they have loosened up. If so your over pressuring for the brass used, and need to back it down. I don't load for that caliber, my mag rifle is a Rem 7mm Mag.

You can run a water volume test to compare the cases. I do it all the time when I have several head stamps. Then I adj the load according to percentage difference.