JES re-bored a 336 Marlin 30-30 for me, that I had saved from the hands of a Bubba. The bore was scarred and useless. JES made it into a 35/30-30 and it turned out great. His standard offering is a 3 groove barrel, which turns out is very accurate in my rifle. I was so pleased that I just had him re-bore another one for me just recently. I had a nice 2002 model 336 re-bored to 38-55, this time with a with a 4 groove barrel, which costs a little more. The 3 groove does fine though, I just wanted to be different this time. I haven't shot it yet, but if it's anything like my other one he did, I'll be happy. The only restriction on a re-bore like you are proposing would be barrel thickness at the muzzle. If the current muzzle is too small, he may have to do extra work shortening it back to where the thickness is OK, and re-installing the front sight, which costs extra. Since yours is a .308 you probably will be fine. I measured my Model 99F in .243 to possibly do the same conversion and it was just barely too small. I think he requires a barrel that is .200 outside diameter over bore size. This means yours would have to total around .559" OD at the very muzzle. Don't believe me, you need to call JES and ask the man. Leave a message and he will call you back.
Last edited by reivertom; 03/22/20.
