Misfeeding and lowered range

[yellow_fever]

A buddy of mine bought a JLS FN2000 about, oh, two months ago. Now suddenly it's misfeeding (on auto it's not shooting anything then spitting 3 or 4 BBs, on semi it's skipping every other round). Also, the rounds it does fire are just sort of rolling out of the barrel. They go maybe 30 or 40 feet and then drop, regardless of the hop up's setting.

Initially, I thought that either the hop up was missing a spacer or a bucking (since there was no tell tale bump inside the barrel while the hop up was on), there was lube in the barrel/hop up, or that the feed nozzle was busted.

I took it home, took the hop up apart and everything checked out, except that someone had accidentally installed a new tight bore barrel upside down (obviously the reason for the hop not working). So I fixed that, made sure the feed nozzle was intact, and put the hop up back together last night, making sure there wasn't any grease or anything in it.

When I test fired it this morning, it still wasn't feeding right for some reason, and now I have no idea why.

Any suggestions?

[azsworst]

compression? Dirty barrel?

[yellow_fever]

The spring is winding, and I cleaned the barrel and hop. That's why I'm stumped, there seems to be no issue, but it's still not working.

[Farslayer]

Mags?

[yellow_fever]

Like what kind? Or brands? Cause it can only use hi caps without modification (the biggest reason I never bought one).

When the problem started, my buddy was using the mag that came with the gun, but to check I jacked in KWA mag and then an Echo1 mag, all to no avail. All three worked before, too, so I don't think the mags have anything to do with it.


BTW, I was thinking on it, anybody think maybe it could be a busted O-ring around the piston? Like a bad air seal? Or is that way off the map?

[dejavu]

have you double-checked the hop up to make sure that it's properly aligned?

I was having a problem just like this with my M4 after disassembling it, and finally, after taking it apart and putting it together 4 times in the middle of a game, I got the hop up unit to line up correctly with the barrel notch and the bucking. Once I got it just right it worked perfectly.

[yellow_fever]

Yeah, I completely disassembled and then reassembled the hop. It's a pretty snug fit once it and the inner barrel are installed. And just through frustration I removed and replaced the whole assembly like fifteen times.

[airbornemedic]

Hey man just to let you know i got his FN and the problem was that the gearbox was broken.

[AxisOfOil]

tappet plate or sector gear? just for the general knowledge purpose.

[airbornemedic]

It was the gearbox itself. The front of the gearbox that holds the cylinder in place broke off. If i can i will put pics up it is kind of wild.