what ammo do I use?

Question
I know a man who has a reproduction Springfield "trapdoor" chambered in .45-70 that has never been fired. I know that the originals were for black powder loads and modern loads were often too powerful and blew the door open. Would it be safe to use modern loads and if it is, what do I use? Any help would be appreciated. Thanks

Answer
If the weapon is a reproduction model it should be fine to fire modern ammo. In Either case, I strongly suggest carrying the gun to a qualified gun smith before firing any ammo out of it. A qualified gun smith can spot problems with the barrel or firing mechanism and could advise you if the gun was safe.