I slugged the barrel on one of my Mosin's and it came out to .312" lands, .314" grooves. At the time, there wasn't a selection of bullets for that diameter so I used .308 Sierra MatchKings 150 grain hollow point. I started from the very bottom of the Sierra load book with Varget and was pleasantly surprised. The rifle shot so well that I never bothered using a different diameter bullet. Now it uses Sierra 165 grain soft point boat tail bullets for any game in arizona. I gave it a trigger job ($5), polished the crown ($20), floated the barrel ($10), installed a receiver mount scope ($150), and full camo paint job from wally world ($30). It is the short barreled M38 carbine and I love shooting it. If you have a sticky bolt, you might try a .30 caliber chamber brush and a drill motor. Put some acetone in there and it will pull all that crap out. Good stuff.