I'm getting under 0.5 MOA with my 260 shooting 143 eld-x at light loads for my son. 2605 FPS. 43.0 grains H4831SC, Rem 9.5 primers, Lapua brass, 24 inch 8.5 twist Chanlynn barrel. It shoots higher velocities well also and it likes the 140 HVLDs from Berger with H4350 even better but I stuck with the Hornady bullets for various reasons.
I'm paying attention to this thread as my wife would like me to switch to copper bullets for a variety of reasons (bird / scavenger health; kid's health,...). She supports my shooting and hunting and enjoys the meat for the family so who am I to complain about another load development project?
Any all-copper bullet recommendations for my 8.5 twist rate? When my son can hunt with it he'll be kept to 300 yard shots, though I'd like options to 500 yards with this rifle so long as velocity for expansion and energy are adequate for clean kills (and he'll be allowed to stretch distance as his skills and confidence grows). This is our antelope rifle for now but when he's old enough I'd like the load to work well for elk at shorter distances also if needed for him (I'd be using 300WM for elk when not muzzleloader hunting).