Mossberg 930 JM Trigger Issue

[Steve Moneypenny]

A friends Mossberg 930 JM tends to have the trigger get heavy once in every 10 rounds or so, we cleaned it.. and I'm wondering if there is something up with the safety. I can see how it may possibly hang down, and I know there are a lot of known issues.. however this gun has quite a few thousand through it and runs excellently.

[mpom]

I would remove the fire control group by removing the 2 pins and pulling the trigger guard out. Dry fire the group at least 10 times, which should result in a heavy pull at least once, based on your post. Hopefully you can see what, if anything is causing your problem. Its no big deal to further disassemble the mechanism for cleaning, inspection and lubing.

Mark

[Bidah]

I would do the above first.  After shooting mine for a while, I would now and then get a "dead locked up trigger", and would have to rack it again to get it to work.  I also found that it only happened to me; the other two that were using it did not have this problem.  Finally figured out that I was riding the safety, and sometimes would not completely flip it off either (my first round lock up issue).  Drove me nuts for a while till I figured out what "I" was doing wrong..   May not be your problem though..

[logiztix]

Riding the safety can also dig a burr into the aluminum block directly under the safety button where it contacts the stamped steel transfer plate, making the problem eventually appear. The only 930 I've personally seen with trigger issues was owned by someone that would regularly forget the safety when the buzzer went off. He would keep his finger smashed on the trigger and try to move the safety, not realizing he was doing it. It was difficult to diagnose originally until I watched him lock it up and saw the internal damage from repeatedly doing it.