Was this a USED Remington 742? Just curious. Since they can't be cleaned with a 'solid' rod from the chamber end, they get cleaned (by most people) from the muzzle end and - invariably - the crown gets all oblong shaped in no time. May 'look' fine, but pretty much a guarantee it'll need to be recut if you are getting a used one from somewhere/someone. My buddy in Oklahoma got one that shot as poorly as you described and that was the issue. Lopped off an 1/8" of barrel, re-crowned, and Bob's You're Uncle!, it was shooting great again.