I know a guy who had the same rifle/chambering and had the same accuracy issues. He tried everything he could think of-bedding, scopes, mounts, a large variety of bullet/powder combos. IIRC, the only bullet he could get to show any promise was Hornady's 100gr. roundnose.
Were it mine and I had my heart set on keeping it, I'd send it to E. R. Shaw for a new stainless barrel ($240+ $115 for installation).
Ouch, lets not get hasty....
...OP, can you show some pics of the rifle, groups. What scope and mount set-up are you running right now? Is it a pushfeed or a classic CRF?