The barrel was sanded and polished on a wool wheel. I just keep it oiled. Been that way for 2 years and no rust.
I spent A LOT of time tweaking that rifle. I bedded the stock, added pillar beds, little upward pressure on the barrel like the Finns did and Timney trigger at 1.5 lbs. It was a fun project and is one of my favorite rifles to shoot. It's not like my .308 target rifle or anything but it often shoots sub 1" 5 round groups at 100 and has been just over 1 MOA out to 400 yards. Did that only once and on a bad day. I'm hoping to improve on that next time.