I am working on an H & R Model 922 pistol. It is the 2.5 inch. The issue was with the cylinder stop. I thought it was worn away as it did not lock the cylinder in both rotation directions. I took it apart and saw that is was a two pin. I ordered the part a two pin but I also ordered a one pin. The replaced two pin just locked the cylinder and it could not fire. Apparently it would not disengage. I changed it and put in the one pin and the pistol would cycle correctly. However the trigger would stick back between pulls. With a little assistance it can be assisted forward and would fire again correctly. Any idea what may cause this?