Have some cratering using 25.6gr Benchmark with Nosler 55gr Ballistic Tip with Remington SPS 700 - Very Accurate load - 2 on left of pictures are Reloads 2 on Right are Factory - Does the Cratering Look Severe
I love BM for the 55gr but Varget is "almost" as good and never shows pressure signs. I have to be careful with BM because MAX creeps up fast and below what Hodgdon shows in their manuals for my Howa 1500 bolt and RRA AR15.
Looks just like my .264 Win. Mag. I had built on a Win. 70 action. The hole in the bolt face was way too big. A 'smith did a hard chrome plating job on the last 3/8ths inch of the firing pin then ground it down to about 2/1000ths smaller than the hole's diameter.
I've seen large rifle primers with very rounded edges indicating a mild load actually have higher peak pressures than SAAMI specs. Such is life with hard, thick primer cups. Soft, thin cups will show their edge sharp at very low pressures. All of which makes it hard to generalize that primer shape after firing is a good indicator of pressure.