J9 Double feeding

I have a Gen9 with a new nylon box all standard apart from the oring and spring, 7.3mm barrel constantly getting double feeds. Using warinterest whites, ausgel yellows and AKA gels. What am I not seeing?

The only thing that springs to mind is mag motor may be running fast or your tappet is back too long

Are you running a 3s battery?

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Yeah turnigy 3s. Never had this issue with the old box running the same. Might swap out the tappets and see what happens

Test with another mag first

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Tested all my mags. Feeds fine on Gen8 and gen 9 and only double feeds on LDT mags

Maybe the motor in the LDT mag has higher rpm, so it forces extra gel in with 11v battery o.o?

That’s what I’m thinking. Probably just annoying more than a real issue.

Just spitballing here, but if the mag motor runs too fast would it feed more than one gel into the t piece breech? Do the gels in the feed tube get pushed past the t piece and sit in the barrel?

I thought one gel would be all that could be in the t piece at any time, but I’m happy to be re-educated. I thought my M4 was double feeding but it was splitting gels in the t… looked like two though.

yes and it really depends on the gels…

if you get one that is massively oversized then everything after it gets compressed. if they are shitty gels, they are likely to get mashed.

if the original first is ok in size you get a couple fed into the t and barrel which results in multi fire but not in a cool way.

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Shooting into something soft confirmed it was two gels at once. With mine it was happening with 2 different batches of ldt milkies, ultras, alphas and armourtechs. Not sure if it was happening with my old gear box but it definitely only happens with the ldt magazines.

Gen8 mags feed faster than the gen9 does, as gen9 has an extra cog in it to slow it down.
Assume your testing in semi-auto. Do you get a gel on every stroke then a double or does it fire empty sometimes?
Pic of the mag terminals on the LTD mags be helpful. There is suppose to be some faster feeding ones around that have large terminal pads top of mag.


That’s all 4. They all do. Gen 8 and 9 mags work fine.

how far do the gel stoppers protrude into the feed tube on the ltd mags?

Enough to stop the gels coming out. I don’t run them on any of my other mags anyway

did you just answer your own question

How would they affect it though? I don’t have them on any of my j8 mags gen 9 has it and ldts do.

i took all mine out too as they stuff up the feeding if they a little big or they don’t get pressed in far enough. Being gels are bouncy and you squeeze em past that stopper would make sense the pop extras in during feed cycle.

Yeah when i was using the j8 mags in a bingfeng viper the top of the magwell use to flex causing them to jam. I figure its that or the tappet spring. I’ve pretty much lost semi auto with this one (it’s been an absolute prick of a box). Might rip one of the stoppers out and see what happens. Just sucks because the gels come out so close together they smack into each other.

ACRs have a floorplate in the mag well that flexed upwards in my 2, so it did not press them in far enough and even after i glued floorplate in was still kind of shit so i took them out and it sorted it out

Floor plate o.o?? Where about is that located ?