Answer

Look at the lock up. Is the bolt locking up? Is the slide going far enough forward? I would think omething is causing the trigger to disconnect. pj

Question Follow Up

Everything appears to be locking up just fine. Run dummy rounds through, bolt closes, in battery, rounds cycle, but no “fire.”

Answer

Confused on the description, you mention the trigger not releasing. What exactly does that mean? You can’t pull it? It doesn’t reset? You pull it and nothing happens? No click or firing pin firing?

If it works out of the gun and not in it, I’d suspect binding on the stock or possibly twisting of the trigger assembly in the stock. Or is the firing pin simply not protruding far enough to strike a primer (depends on what your description means)? Jeff

Answer

When you cycle the action the trigger is disconnected so the gun cannot fire. When the cycle is complete and the action is locked up, the disconnector is supposed to come off. It sounds like it is staying disconnected. Out of the action the trigger isn’t disconnected so it can fire correct? When you install the trigger group it would appear that it is being disconnected. I would look at the disconnect system for any problem. At least that is where I would start.

Question Follow Up

Upon further pondering and inspection, determined that the action bar lock spring is broken, allowing the action bar lock to move upward when installing in the shotgun, thereby moving the trigger disconnector to the disconnect position and removing the trigger bar from activating the sear. Thanks to all for the help/suggestions.

Answer

That would do it. Good catch. Jeff

Answer

Also check to make sure the forearm nut is tight and holding the forearm in place. They can get loose and the forearm moves back and forth and prevents the action bars from moving forward as far as it should and the action bar lock cannot get behind the action bar. So the gun never reconnects. Ken