i have a winchester classic and no issues with it.
i do also have a winchester p/f l/a that i had a lilja barel screwed on and the bolt face opened chambered in 300 wsm.
if i put 2 in the mag, sometimes when ejecting the hand loaded round out of the chamber, the top round pops out of the mag.
never could figure out why, but it sure runs fine as a single shot !
any help how to solve this problem to get it to stop popping rounds up out of the mag ?
Your rifle's rails, ramp and follower/spring are probably configured for the original cartridge. Properly altering the rails and ramp, and a new follower/spring would be the fix--just be careful, it's an art that even many otherwise good gunsmiths aren't all that familiar with.
Casey