I believe that bulged barrels come from trying to "shooting out" a previously stuck projectile with another round with another projectile. A round (brass + powder + primer) with no projectile will easily "shoot it out" with no ill effects.
Ever watch a Scheutzen benchrest match - virtually all these guys "breach seat" their cast lead bullets separately with some kind of a lever acting bullet seater - engaging the bullet at least half the bullets length into the rifling. Then they insert a primed / powdered case (usually plugged with some kind of foam or cork gasket) into the chamber and fire it. I recently tried this myself and although apprehensive / skeptical, it actually works fine and for cast lead bullets at least, there's a definite accuracy improvement
Ever watch a Scheutzen benchrest match - virtually all these guys "breach seat" their cast lead bullets separately with some kind of a lever acting bullet seater - engaging the bullet at least half the bullets length into the rifling. Then they insert a primed / powdered case (usually plugged with some kind of foam or cork gasket) into the chamber and fire it. I recently tried this myself and although apprehensive / skeptical, it actually works fine and for cast lead bullets at least, there's a definite accuracy improvement