This beauty needs to perform to it's potential since my 7mm Rem Mag will push a 140gr @ 3350 FPS with RL22.
It is a 26" 1-8 twist.
So far I am getting my best results with 64.5gr RL25, but that puts me in the 3100 FPS range. I used to get 3250 FPS easy with another 264 WM years ago with H870. But I don't have any H870 anymore :( When I ran out of H870 with that rifle I used 64gr RL25 @3090 FPS in that one with good accuracy.
Groups seem to open up @ 65gr RL25 :(
I am 10 thousandths off the lands
So you 264 fans need to help me out. I am especially interested to see if anyone is using Retumbo or US869 with favorable results.