Picked up an mp9 with a broken disconnecter, replaced it with a Wii-Tech steel one. I have 5 mags, all of them do the same thing.
It’ll fire the first 4/5 bb’s, then it’ll dry fire turning the gun into essentially a bolt action. I noticed that if I remove the bolt assembly and reinsert it some times it’ll go through two whole mags and then the third would do the same as above, fire a few bb’s and then dry fire.
Mp9 is completely new to me, so I’m unsure of what to check. The nozzle seems fine, the feed arm isn’t snapped or broken. Unsure what else to check?!