AR 9mm trigger won't reset

[TEN-X]

I built a 9MM on a Gun Point lower, Anderson upper, CMMG bolt Mec mags and 7.4 oz buffer. RRA 2 stage trigger would not reset. Tried a mil-spec DPMS. Will function with the safety removed but not with it installed. The lower looks really good and is well made??????????????

 

[Hit and Run]

Check edges of inside of sainfety walls for accessive rubbing. If rubbing a bit of sanding/filing may work. But very little, recheck, slow process....

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[frogman68]

Are the pins walking out ? My YMH was doing that took it apart confirmed the spring fit in the groove in the pin reassambled. Still walked so I put some no walk pins in it .
The firing assembly is put together correctly ?

 

[GolfR]

Will the trigger release and reset with the upper off?

 

[5.56blaster]

Do you need to use a 9mm hammer? I built a 9mm lower, used a 9mm RRA hammer and no issues. Just an idea.

 

[kalister1]

I had a safety that was too large in diameter to allow the trigger to rise up enough to reset. Check for burs and/or try another safety. The trigger could e too large, same issue, trigger or safety?
If it works fine without the safety, look there.

 

[Sticky]

Is it possible that the disconnector spring is upside down? It is tapered, the fat end has to be down into the trigger relief fully..

 

[TEN-X]

Got it working!

I fired about 40 rds with the safety removed and broke the bolt catch. I've read this is a common 9mm problem. Reinstalled the RRA trigger and took about .002 of the safety flat. At the same time I got my 10.5" upper together. Installed it on the same lower and it functioned with or without the can. Put the 7.5" upper back on; would not reset....... soooo I swapped the 7.4 oz buffer for a stock and then an H2, and it worked. If I was building this for someone else I would have had to charge them $1000 labor and $500 for ammo!!!
Thanks, everyone for all the input. I learned some new stuff.