Chiappa m4 22 problem

[mikeytapz13 0]

Heres the scoop on performance...brought it to the range 120 rounds no problems at all...load up another mag, pull the charging handle...click,click...nothing..release the mag, clear the chamber ...i take a look and apparently the bolt did not release and is stuck at the open position...i spent 20 minutes trying to figure out the problem. Finally i shoulder the rifle and it charges no problem...couple more rounds no problem...load another mag, and the same issue. Frustrated i go home to see what the problem is...seems like the upper does not fullly sit on the lower... However if u add bit of downward pressure onto the upper, the bolt will then work...perhaps why it worked when i shoulder it....is this common for 22 builds, common for ars? I dunno if its me of the rifle. I own a sig556 never had 1 problem...any input?

[twong11219 0]

Seems like no one chimed in on this. I'd recommend doing a thorough cleaning. Upper, bolt and lower action including the bolt catch. Based on what you're using, carbon build-up can get pretty bad with 22s. Considering that you jiggled the upper and lower, then everything worked fine, I'd say there is something causing the bolt to stick. The first things I would look at is the bolt catch and hammer. Those are the 2 parts within the lower that contact the bolt. I think the Chiappa has the bolt lock function but not exactly sure. If you depress the bolt release, and the bolt is still back, then possibly the hammer spring is too heavy for the 22 bolt assembly. Disassemble the upper from the lower and try to cycle the bolt to see if it slides smoothly. If so, then maybe the hammer face needs a bit of lube, recoil spring might be weak or hammer spring too heavy. Maybe polish the contact points of the bolt to the hammer to help smooth out any tooling marks.

 

Check the mag if there is one in particular that is causing this issue as well.

 

Good luck.