Mine are averaging about .311...should be good thru the .310 barrel without sizing them. However...I will also try them thru my .309 sizer with gas-checks. I don't have a way to install the gas-checks without sizing the bullet, but if it looks like they will work well in the 7.62 barrel, I might get another sizing die from Lee. I need one anyway, because then I could also use these bullets in my M-44 Nagant. I also have another old spitzer 2 cavity mold that I got at the gun-show, but it is missing the sprue plate, I need to send it in to get re-fitted. It is throwing appx .313, and makes both a small plinker, and appx a 180 gr bullet. This mold could be meant for casting a two-peice soft-nose bullet, not sure....Plus...my 175 gr Lee round-nose might work well.