When I had my 7x57 M70, I was using data out of Hornady's #3 manual. Compared to everyone else's manuals, the data was HOT! I had no excessive pressure signs out of my rifle, and I was loading on an RCBS Junior press, and noted no more difficulty in sizing the Winchester cases, either. That press hasn't got the juice a Rockchucker has, by any means.
Didn't matter, it killed coyotes and deer without drama. I was running a 139 SP at 2860 fps, roughly the same fps. I was getting out of my .270 with 140s (I loaded it pretty mildly). Same weight bullets, more or less the same diameter bullets, same effect on critters. Big deal.
