Look at the muzzle, Is it bored larger than the rest of the barrel? Are there any nicks or dings on the muzzle crown? If not you can probably hang it back on the wall. If it is counter bored it's likely it is shot out or badly corroded. It can be recrowned but you can get another cheap enough to not bother with it. They are a piece of History and can be quite the conversation piece. You can always take it down and clean it when young gentlemen come calling on your daughter.
"War is an ugly thing, but not the ugliest of things. The decayed and degraded state of moral and patriotic feeling, which thinks nothing is worth war, is worse. A man who has nothing which he cares more about than his own personal safety is a miserable creature, and has no chance of being free unless he is made free and kept so by the exertions of better men than himself" John Stuart Mill