You were fortunate to get all back to normal. A friend of mine once was shooting roundball out of his .50 caliber CVA Hawken rifle. Well he grabbed ball from the wrong supply he had. He also shot .54 caliber out of a Lyman rifle. Long story short, he some how got that .54 caliber .530 down under the muzzle in that .50 caliber rifle.

When he finally called me and asked what he should do I told him to take it to a gun smith. Well instead he tried to drill it out. But he was not a perfect 90º goin going in. He got the ball cut enough to bring it out in pieces, but when I checked the bore, it had a huge gouge down along the side of the barrel about three inches down.

I suggested he cut the barrel down three inches and then cone the end. But he's still been shooting that .50 with a messed up muzzle. So you were real lucky. Or a good driller.