From the look of the rifle, on the hammer side, it appears to have a similar locking mechanism as my 1873 Springfield Trapdoor. If that is the case, then one of two things has happened. 1) the locking teeth on the hammer has worn down and can no longer engage the spring that sits underneath it. 2) the spring underneath the hammer has broken and will need replaced. The only way to know for sure it to take it apart and see.
Should you decide to take it apart, make sure that you lable each part and where it came from (works for me everytime
). Once you have it apart you will be able to work the components and observe their action. This will tell you what is wrong with it, and then you will be replace the damaged component. Nine time out of ten it will be the spring.
Let me know if this helps or not.
The difficult I do immediately, the impossible takes me a few minutes longer.
NRA, U.S. Army (Ret), AGA, F&AM
A Person has to stand for something, or they will fall for anything.
How different the new order would be if we could consult the Veteran instead of the Politician - Henry Miller
The Soldier, above all other people, prays for peace, for he must suffer and bear the deepest wounds and scars of war. - Gen. Douglas MacArthur