I have had 4 different .257" caliber rifles.
Two built before the fast twist and heavies were around.
.250AI (.250-3000 Ack Imp 40°) pushing a 100SMK/100TSX @ 3100 or 115 HVLD @ 3050. Killed a few deer, javalina, and a coyote at 1327 with it.
.25-06AI pushing a 115 HVLD @ 3450 or 100TTSX @ 3600. Killed a bunch of deer with it. 800 rounds are barrel was toast.
I now have two fast twist rifles to push the heavies. These are a gamechanger now.
25 Creedmoor pushing a 135 Hyb @ 2975fps. I but it to be a alR steel rifle, but woukd have no problem shooting deer with it.
25SST (Serman Short Tactical) pushing all 3 of the heavies. 131 BJ @ 3126 (had them up to 3350+), 135 Hyb @ 3127, and 133 Elite @ 3199 (had them up to 3365). We have killed a few pronghorn with them at 331 (131BJ) and 875 (135 Hyb). I hope to put another down with the 133 Elite this year.