This looks like one of the "Tower" repro's from the 60s? As was voiced earlier, there was some real "junk" put on the market and before shooting this one, you should have it checked out by a good gunsmith who is familiar with black powder weapons. I've been involved in BP shooting since the 60s and with ANY gun, SAFETY comes first! It's been a long time since the 60s, but I do remember the brand that the one fellow that responded is talking about and they were definately UNSAFE - real junk and an accident waiting to happen. I also remember a flintlock pistol that was put on the market (I'm sorry but I can't rememvber the brand name) that actually had the breechplug "pinned" into the breech of the barrel instead of being threaded - obviously a safety hazzard and after a number of mishaps, they were recalled also. If I remember it right, the breechplug was tapered and pressed fit into a corresponding taper int he breech of the barrel and then "pinned" throught he barrel walls and breech plug. Whoev er the idiot was that thought that up should have been made to shoot them and experience the plug shearing the pin and blowing backwards in the direction of his face! Play it safe and have it checked out by a good gunsmith - even if it checks out, it wouldn't be a bad idea to "proof" the barrel - i.e. - remove it from the stock, secure it to an old tire pointing it in a safe direction and put a load and double ball in it, use a piece of fuse and touch it off with you being in the distance - a very safe distance in case it should blow. If the barrel blows - better that you loose the barrel than your hand or eyesight! Even with a new barrel, when I am building a muzzleloading rifle, I ALWAYS proof it with a heavy load and double ball and then check for any defects - splits, bulges, strength of threads on breechplug, etc.
I remember the pistols like yours being around - if the barrel and everything else checks out O.K. - I think one of the problems with them was also a problem with the frizzens not being hard enough to cause sparks - if this is the case, a good gunsmith should be able to harden the face of the frizzen so it will throw good sparks.
Good luck and as always in this hobby - play safe!