Standard Velocity
Winchester 296 and 748 are dirty powders as well. I have never broken in a barrel in my life. Just shot them and cleaned after a shoot.never had a problem.
Now days I use cfe223 and my son's 222 rem hasn't been cleaned in 300 rounds a mind still shoots half to three quarters of an inch at 100 all day.
Don't get me wrong a lot of people run their barrels in and good on them if they find it works. Modern stainless barrels one my rifles are hand lapped so should be smooth to start with. To me every shot I put down the barrel running it in is one less I can shoot at game and the sooner I have to replace the barrel.
This response will get me in a bit of doggy do-do but that's fine it is only my opinion .
200 yard group out of my 25. The barrel is a llijla match grade stainless. Never run in, sighted in and shot.
