For a Whelen I loaded some 250 speers over this stuff to figure out pressure, and also some 310 woodleighs. Unfortunately won't be able to shoot it for a few days.
About 58 grains will fit into an unfired norma/nolser case, pretty high up the case neck, but with the powder settled with a high-end vibratory device (electric toothbrush), I couldn't feel any or hear much compression under a 250 Speer at 3.35 COAL.
Probably get a little more into a fired case. Less if you seat deeper. From memory, I think the same cases hold about 60 or 61gr of RL-15 at that COAL without crunching.
I have pretty good data from this same rifle using RL-15 for various 250's. I'll report back.
