Formally known as the .257 Roberts. A good old friend just picked up a nice Mod.70 in the .257, and we're going to work up a load for it. I just got the dies and 400 Speer 120gr. btsp's. Will be using H4895 since I have lots on hand. Nosler load data says start @30grs, max @34grs.
https://load-data.nosler.com/load-data/257-roberts/
Michigan white tails out to about 200yds. is the goal. So, anyone have experience with this fine old cartridge? I see some +p data floating around, but I doubt we'll be going there. What say the collective? Any advice going forward would be greatly appreciated.
https://en.wikipedia.org/wiki/.257_Roberts