Need help, I think I have a problem

[RGRJM]

Just finished assembling lower. Went smoothly. I did a function check. First step is OK. The hammer catches the sear detent and hold, pull the tigger and it flys forward. But when the hammer is pushed back, engages the disconnector and i let off the trigger, the hammer should catch the sear and hold. But it flies forward. I checked the spring under the disconnector, it is big side down. The disconnector pivots. Everything checks. If i push down on the disconnector a couple of time, flexing it, the hammer will hold. It almost seems like the trigger spring is not pushing up fast enough to engage the hammer catch. If I apply a bit of down pressure to the hammer as I let off the trigger, it will catch and hold in the cocked position. I think this would cause some "unpleasant" things to happen if I let off the trigger and the hammer won't stay down and there is a live round in the chamber. Any thoughts?

[Tweak]

is your selector in place?

[RGRJM]

Yes, the safety selector is in place. I put it in pointing to fire with the hammer cocked.

[Tweak]

with the trigger forward cock the hammer so that the middle hammer hook is near the tip of the disconnector. How far apart is the tip of the middle hammer hook from tip of the disconnector?

[spamsammich]

Have access to a known good FCG? Swap in parts until it works. If nothing works, you may have an unfavorable stacking of tolerances in your lowers hammer and trigger pin holes.

[RGRJM]

Took some measurements, disconnector grabs a max of .020 of the upper hook. The distance to the second hammer catch and the disconnector is about .030 when the hammer is pushed down with the hook directly opposite the disconnector, trigger forward. I found out that if I ride the trigger forward, with the disconnector engaged, the hammer will slip past and fly forward. If I let go of the trigger sharply, it will catch. So, I wonder if the disconnector is sitting too far back, and geometry needs to be changed so it rotates farther foward to grb more of the hammer hook - or - the trigger assembly needs to move up, as in a new one.

[Tweak]

the tip of the disco should almost touch the middle hammer hook, so close it will look like they are going to touch.

I'd suggest swapping in parts before you grind on anything.

[RGRJM]

Yeah, I think so too. What a pain. Thanks for your help.