I have a 33" barrel on my .50 cal. and I find it takes 70 grns. of 3fff KIK to shoot a 2" group at 50 yards, to me I think it has a sharper(harder) recoil than my brother 42" barrel, but a PAST Pad helps out a lot. If I was you I would leave it as long as possible unless it is unwieldy, then I would shorten it by 1/2 or 1" sections until it just kinda "hangs" on the target then I would stop cutting and leave it as is. Btw, It looks like I'm going in the opposite way. My first rifle has a 33 1/2" barrel, my next is a .40 cal. 36" Mark Dehass squirrel rifle, and now I just purchased that .40 cal. 38" Colerain swamped barrel off the want ads for a future project, it will be my first swamped and Colerain barrel.