I know of a handi rifle that was a 45 Colt and the owner reamed it to 460 S&W, with 200 gr. Bullets he got a little over 2900 fps with loads worked up with quickload computer program.
Another friend had a 32" barreled H&R Buffalo Classic and reamed it to 45-120 and loaded 40 cal. Bullets in a 45 X 40 cal. Sabot for a muzzleloader . He got 3000 + fps with light bullets.
Not sure it would be worth the bother gain a few hundred fps ?
Im in OH also and if I had a spot to hunt where a 200 + yard shot was possible I would sight my flattest shooting legal rifle at 200 yards and work with a range finder to find the real trajectory your rifle has. If you had a 100 - 125 yard shot you would have to hold quite a bit low but if you had the time to " range " your deer and had a solid rest you could snipe deer at long range if you had the right bullet that expanded at that remaining velocity. A flat nosed cast works good even at low velocities but has a bad BC for long range, a pointed J bullet will shoot flatter but might not expand at 250 yard velocity ?
straight walled cartridges and long range hunting is a tough nut to crack.