M4a1 gears replacements

Hey guys, I need some help I have a gen 9 m4a1 that I managed to strip the gears on everywhere around my area has all sold out of all the “proper gen9 gears”, I’m just wandering if any gears would work like nylon gears from a wells M4 or something like that TIA

Hey Patrick, welcome.

I’d just be inclined to grab metal gears some via post.

Not sure where your build skills are at but shimming would be mandatory, lots of really good vids out there for that.

The wells gears, should drop right in but then you’re robbing one blaster to fix another and what’s the point of that?

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I’ve watched all the videos on how to insert metal gears and shim them all correctly I do plan on buying them eventually when I can afford it as well as another nylon case and just have it as a side project, if the wells gears will fit that’s great news I can buy them today

The gear shaft might be a different diameter? Take one of your damaged ones with you so you can check the dimensions

EDIT: Take all the damaged gears with you to make sure theyre the same dimensions :+1:


You will probably also need to grind a couple of teeth from the front of the sector gear and the rear of the ladder gear to match.

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Thanks for all the responses I was able to get my hands on some gen8 nylon gears I had a go at putting them in this morning, however everytime I put it all back together and test it it seems to grind with further inspection I found that the way the gears are spinning they are only pushing the plunger forward not actually dragging it back so It can fire, so I’m not sure if I’ve damaged my motor and it’s spinning the wrong way or it’s just something small I’ve missed I’m going to give it another shot when I get home

You most probably fitted the connectors on the back of the motor the wrong way round

@Rattler if you mean the positive and negative on the motor I definitely have them on the right side I triple check it when I was putting it together so I don’t think that’s it I’ll double check it again when I’m home

So I was playing around with the gearbox again tonight and stupidly learnt that my gear box was fine the whole time as soon as I took my spring out which is the same one I’ve used since I got the ■■■ which is a 1.3 spring it fires beautifully, I now however have no idea why it’s deciding not to work with my gearbox could anybody point me in the right direction please