Lots of guys on here swear by RL 22 in 257 wby. fed 215 pr. 100 tsx, 110 accub, 115 b-tip, 120 part. etc. I havent tried it yet. I tried RL25 from 70 to 74.5 gr in wby brass fed 215M, 110 accubond. In my submoa all the charge wts shot pretty well. I have settled for now at 74 gr at 3400-3450 fps. OAL 3.25 i think. I don't have much drive time with the 257 yet. there is alot of data on here if you search the threads. Reloaders nest is another source as well as realguns.com Good luck! Maybe some of the more seasoned 257wby guys will weigh in with a more qualified opinion.
