AR double fire and reset issues

[Moleman-]

Figured out that the hammer is not catching when the BCG slams it back. Gonna order a new trigger group and see it that works.

Why is that happening though? This kink of malfunction comes up quite a bit especially when the kits are cheaper or there is a higher demand (more junk gets through). If the FCG springs are installed incorrectly the FCG won't work correctly. The disconnector spring in particular is often installed upside down. The bottom of the spring is supposed to go in the trigger pocket to make it stay in the trigger when the trigger or disconnector is removed. If it is placed in upside down the wider section will lock into the disconnector and trigger pocket and hold the disconector back or cause it to be "sticky" so it occasionally doesn't work. Also if the disconnector pivot hole is off slightly the disconnector may not pivot forward enough to grab the hammer. There is a fitting tab on the front of the disconnector that will allow for some adjustment to gain a little more contact with the hammer. No sense buying new parts if you don't need them.

[Jimbean96]

Bought used from another MGO user. Pretty disappointed this issue wasn’t mentioned. Unsure of the brand of the trigger group but the lower is PSA.

[westcliffe01]

This is a very common outcome when one tries to lighten the stock trigger. Modern triggers have the actual sear in a totally different position and the original sear position is used as a "safety sear".

Compare to this trigger

[joepistol]

I recently bought a CMC trigger for an AR..the hammer & trigger are both installed in an stamped steel housing..
Couldn't believe how much EASIER it was to install. The special pins that came with the trigger are hollow,
& have female threads cut in both sides of the pin.. trigger set also came with small screws,
to thread into the pins.. no way for the pins to walk out.. What a well-designed trigger!

[Jimbean96]

I thought the bolt catch felt a little odd upon further investigation whoever put together the lower swapped the disconnecter and bolt catch springs around. Problem solved!

[Moleman-]

Thats a new one for me. The PSA lower kits I've put together had everything sorted out in a different bag to prevent that sort of thing. Glad you got it sorted out.

[december1979]

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