He needs to check the intergity of the barrel. Look for any severe pitting.., fractures, ect. You gotta be careful with old firearms. The best thing you can do if you're not privy to gunsmith work.., is take it to a pro and have it inspected. These old firearms can be very dangerous if not given a proper inspection prior to shooting.

I know people that have found old firearms in chests, bookcases, ect., that were 100+ years old and STILL LOADED! I actually know someone personally who's father found an old perc. (cap and ball) pistol. that was quite old and still loaded. The guy was careless, cocked the hammer, and let her go before even inspecting the weapon. The weapon was found in a old damp basement on a shelf (dirt floor basement). All the moisture over the years reeked havoc on that old pistol. When he let that hammer down..., BOOOOOOM pistol actually fired and exploded. He was lucky and had some minor burning and a few cuts.