J9 to v2 gearbox component compatability

Are the only components that are not compatible between a j9 and v2 gearbox the:

As I have recently had 3 blasters die on me, and when i try to use a spare part from another i seem to run into never ending trouble that one problem then causes 3 others.

The rest of this post is me complaining so only read if you enjoy seeing simple solutions turn to shit…

e.g 1: hk416 return spring goes = no problem have a spare … wife lost bottom base plate for hk416 pistol grip, we still try to do this.
Turns out now 2 screws to secure motor in place threaded first time on opening.
Still try, but realise without bottom base plate of pistol grip it gives the motor that little bit of extra support= grinded down nylon motor head. And no shop for hundreds of km sell nylon motor top gear.

e.g 2. ACR-j10:
shop sells me a v2 piston for my j9 gearbox, same story: we try to do this anyways.
turns out you need to dremil piston, 1 month later of it locking up on me mid game, tech then says you need to dremil the j9 gear box rails = desperate as i am i do this.
next game running smoothly untill the gearbox breaks and piston head snapped.

e.g 3: Aug piston seems to be very slightly wider than a j9 piston. Swap it back to original, during this the souldering on aug is shit so need to resoulder , during process i some how melt the wiring getting a x wire somewhere and blaster catches on fire and smoke.
open it up, mag terminals on bottom of gearbox are burnt snapped and melted now to mag. mag wires are melted and merged, aug board (maybe a sort of MOSFET) burnt out one of the chips. Opened up the aug completly to get to all the wiring, broke a plastic plug in the process as this thing kinda isnt easy to pry open.



I really should not laff…these are valuable lessons for everyone


It’s been my experience that blasters can be a royal FPITFA

You definitely need a spot of good fortune though

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Its seriously annoying to not have our tools standardised.
So will I have to measure up everything pror to buying?
Or should i try to search for a compatible piece for every single blaster piece.

e.g aug compatible piston

Is there any other component that isnt cross compatible in a v2 gear box apart form the piston? like cylinder size or gear set?

And is it a stupid idea to try to standerdise my self and jsut go trying to fit a v2 gearbox into everything i have now - or be patient and order everything specifically?


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Your rant above will serve others well in avoiding the same fate

But yes, an actual consistent standard would be grand…what would be better is documentation and drop ship QA

It’s why I only order from a few places…I just got sick of being don’t…we don’t know…you’re selling the damn thing, how could you not know?!?

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fk, it sounds like i will need to do both then.
Measure everything and search for model compatibility.

That is often still not guaranteed though because say i want an aug piston that isnt their standard stock shitty ones that have a grove out of them to even further reduce compression, i couldnt find one that matches aug specific.
Unless the Vector, Aug a3 and Wells all have the same sized fitting parts.
I know that wells and a3 and vector have individual sized barrels and return springs - different to everything else out there.

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Pretty sure I dropped my wells piston into the mk V2 compliant box

Vector piston, no clue. If I remember I’ll check that for you

I can definitely add the Rx akm to your list of does not conform :sunglasses:

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You also have to remember that a gearbox might say it is a V2 in the (ebay) ad… but it may be one of the 7 different types of rip off clone boxes… and lord knows, I have tried messaging the sellers and ask for the dimensions of parts or if they are sure that a part will fit a Gen 9 or a wells or something… but they have no idea what I am talking about… they have never even seen a gel blaster… the sellers are just sitting in a booth in an office building, at a computer loaded with catalogues… when they sell something, they get some money…

that is why you can buy gel blaster parts from a seller called ‘topbeautynails69’ or something… they have been selling (drop ship) beauty ‘equipment’ for ages… but now have signed up for the gel blaster drop ship catalogue as well… there seems to be alot of this gel blaster stuff selling… so now they sell fake fingernails, stick on eyelashes AND gel blasters (whatever they are) dizzy badluck


Always get a giggle out of your rabbits @Calcifer

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You can right click and ‘save as’ to keep them too calmdown fart head drum

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that is so funny despite it being depressing

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So jsut measured up what i was intending to use:

j9 piston: 17.9 inner of rails
20.6 outer rail width

black metal piston: 17.9 inner of rails
21.6 outer rail width

new red metal piston

aug stock piston

So far every single piston is different How can someone work with these variables.
And no more dremilling pistons to fit, that actually just weakens the build and fks things up if not perfect.

As for cylinder measurements of j9 j10 aug and hk416 both are exact same inner diameter and length, not taking into consideration of port.

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The piston doesn’t have to be tight in the cylinder… the seal does the sealing. If the piston were too tight, or should I say, not have enough room to move around a bit, then the seal would not be able to do its two jobs… one of course being to seal like a piston ring, but it is also responsible for covering and opening the piston holes as it goes back and forward.

That is why you have to have a thin-ish seal that seems too baggy and loose on the piston in its groove… and when putting the piston into the cylinder, you have to feed in the seemingly ‘extra’ part of the seal that hangs out.

I tried fitting a thicker O ring to a piston, one that ‘fitted’ the groove perfectly… no slop at all… guess what… it didn’t work at all. When I put a thinner, baggier, sloppy O ring in, it worked perfectly.:+1::grin:

Ok, with my aug build, i changed the aug piston over to that j9 piston, but after 20 shots or so it would jump off the middle rail and get dislodged?
Any idea how to staop that, for me that indicates that it isnt wide enough for the aug gear box.

That would be my assessment also.

Stopping that requires the piston to have taller rails which would be problematic to do at best and a total pita either way

What’s wrong with the stock piston?

for some reason the piston in the aug has a very slight hole or gauge out on the top side of it, allowing for air leak.
I should show you a pic of it but cant be bothered to get my phone and do an entire upload.
it dosnt make any since considering the aug cylinder is also ported.
when i changed over to a standard j9 piston the air compression is awesome, with thumb holding down cylinder nozzle side = no air leak, but changing pistons back to aug it dosnt block it off at all, jsut slides right in dosnt matter what o ring i use.

i think i get what you mean there. building up that small recess would be allot easier than building out on the j9 rails

although and whilst you’ve stated it, i would have gone with better o’ring. that really hinges on how deep that gouge is.

i am definitely curious about the cylinder porting. 70%?

got rid of cylinder with normal one, no compatability there
Just piston, so went back to stock piston, used a green oring but disnt make any different in compression really. Should i use like a super glue and try to mould that head of piston.
Actully that would be a bad idea, i got no idea how to improve it.

build out slowly using something like araldite

slowly…build, file, sand, repeat…many layers makes for a strong adjunct


awesome , thx
post needs to be more than 20 chrs.

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Yea…gets me allot of the time too

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