After I got my 270 back in the late 70's, I read an O'Connor article where he gave 60 grains of H4831 as his load for the 270 with 130 grain bullets. That's where I started out, and what I still use today.
By the way, I remember an article on the 7X57 by Jim Carmichael where he gave his favorite load for it. It was 51 grains of IMR4350 with a 140 grain bullet. That is way more powder than the manuals show today. Those guys must have believed in living dangerously. But, I have loaded and shot Carmichael's load in my 7X57, and it didn't show any signs of pressure.
We all need to take into account that the recommended loading data for old military cartridges typically has a lower pressure ceiling due to the wide range of quality of materials and workmanship found in old military rifles and, in some cases, because of the strength/design of the actions. A load that is safe 24/7/365 in a commercial bolt action might be a potential bomb in an old military rifle due to design flaws, questionable metallurgy of some rifles that were made under sub-optimal war time conditions, or in rifles that were poorly maintained.
I'm thinking in terms of a hot 7x57 load fired from a Remington rolling block or an equally hot 6.5x55 load fired from a Norwegian Krag.
