Retro Arms CNC V2 split gearbox into J10 ACR

HI i am really stumped atm and sick of waisting money i have gone through an uncountable amount of gearboxes and internals aswell as receivers i am trying to fit the retro arms split v2 gel gearbox into my j10 acr now it fits but just falls short for the mag to meet with the t-piece and allow it to feed and shoot i read on GBAs web page tht i needed to get the FB tpiece and adaptor which i did and it still didnt work wenni msgd the ppl at GBA they told me tht it wouldnt work even tgo their web page said tht it was needed then they tried to tell me tht my gearbox was an airsoft gearbox even tho it clearly said on my reciept GELBLASTER then after i showed them tht they told me tht they are currently working on designs for a 3d printed tpiece for the gearbox to.fix into the acr and without it there is no possible way but i have spent too much $ to give up now so please some1 help!!!

Is it in line with the mag but just not going down far enough?
or not lining up at all?

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Gel Blasters Australia is your problem !
If you want some knowledgeable advice ring Kiron at FPS blasters 0402146258.
There are very few in this industry that have any clue at all and GBA is one of the worst!


second that rattler. they won’t even accept my money lol because I’m a Vic resident. told them on the phone “this is discrimination.and its unaustralian what coz we (Vic’s) love AFL over NRL” then quickly hung up before he could say it’s the law lol


well technically is Airsoft GB the t piece and barrel are only difference between their version and ours. all other gearbox internals are same. but still wrong how they treated ya. look on the bright side the retro has a crazy box😉 so definitely backed a winner there. I know there almost a drop in to the JG slr receiver minor tweaks this is link its made for gel blasters the gearbox isnt airsoft as far as i can tell if so why wuld they pyt gel blaster in the title

It is specifically an airsoft gearbox, a lot of the gear we use is airsoft stuff that is compatible with gelsoft. Anyhow, I’m currently working on assembling and installing a one piece retroarms gearbox over the weekend, it’s into a v2 receiver (as opposed to your j10, the differences are subtle afaik, but need to be addressed). So I’ll see if there’s anything I come up with that could assist, but just be prepared to accept that the acr body isn’t exactly retroarms friendly

I wouldn’t be putting one in mine anyway

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Heya bud… What minor tweaks are needed for the SLR receiver?

Dremel out the charging handle otherwise top receiver hits the top of the gearbox and won’t close.
That’s all I found🤙🏼


If it is an airsoft gearbox why is it they advertise it on their site as a gelblaster box ?

Its not inline so since the gearbox is a few mm shortee then the original if the tpiece was to sit in its normal spot there wuld b a few mm gap between the box and the tpiece but if i push the tpiece back to the box the part tht lines up to mag doesnt n e mre i have thought bout extending the tpiece and making the nozzle bit longer not sure if it wuld work and dnt wana waist any more time or money unless i know its deffs gunna work lol

Is it really worth 156 for just the shell?

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I know i wana make it worth it lol

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GBA have a retro arms nozzle thats adjustable, I wonder if that would help?

Because ■■■■■■■ is illegal in Australia, and that ■■■■■■■ designed parts operate under the same design principles that they’re interchangeable with ■■■■■■■. At best they’re just drop in, at worst they take a bit of modifying for what you can buy in store here in qld/wherever.
If they advertise it as being ■■■■■■■ parts, they will run into legal problems.
The v2 gearboxes in the new ldt hk416 are an ■■■■■■■ gearbox version, and I’m fairly sure they don’t play nice with gen 9/10.
And what nozzle/cylinder head are you using? I just recently learned that it’s best to use a wells setup for those bits.

I bought one of those and no… Doesn’t help. Because the tpiece still sits too far forward

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Yea so i was thinking wat if the tpiece was extended back towards the gear box a few mm and then a longer nozzle as well to make up for the few mm increase so then the tpiece can still sit where it needs and pretty much the nozzle can still alow for feeding and can shoot

Did you get this working?

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Yea i di get it wo trking took abit i sent my gearbox to bruisemaster he remilled it and also made me.a custom tpiece and barrel and nozzle to make it all fit

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What cylinder head is used with this? i am assuming a 6mm. Looks great