10/22 failure to reset hammer.

[Diamondback68]

I have a 10/22 in which I installed a Timney Trigger. After a few magazines it will not fire without racking the slide. IE: Insert magazine, rack slide and fire. The second round loads but the gun will not fire until the slide is racked, ejecting a good round and seating the third, which fires Ok, except the fourth round will not fire. Racking the slide cocks and allows fire again. Anyone had this happen?