The hang fires are because your shooting pellets using a #11 cap. Switch to loose powder and all your problems will be solved. Pellets require a large flame to properly ignite. What your doing is throwing a small spark on it that then has to burn powder enough to ignite the entire pellet.

Pyrodex RS will work perfect in that rifle. My LK rifles with the 22 inch barrels like 85-90 grains of loose Pyrodex and they shoot excellent. Try some loose powder and then let us know what kind of problems your having.