Acr motor height

Any tips on how to check the motor and pinon gear are at the right height for the bevel gear and the bevel gear height is right on the ACR J10?


Curious too o.O
Coz the m4 way don’t work since grip and lower receiver is one piece :worried:

I wondered if a gen9 pistol grip would be the same? So you could just set it on that. I’m guessing no.

Maybe someone has a broken acr that could be hacked up to open it all up.

i just put half the gearbox in do same way as m4 and use a bright torch to look. But i also can get a finger down there to check play and rotate bevel gear

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When you say half the box, you mean just one side of it o.o??

Shimacr (1) Yep left side.
Yellow arrow rear pin thru as well as grip screws as gearbox at the bottom maybe different angle to whats at the top of pistol grip.


This is how I set the pinion height on an ACR, you use the depth gauge on your calipers.
I assume you know how to use calipers properly :rofl:

First measure the length of your pinion and write it down, now with your bevel gear sitting in half of you gearbox measure the distance from the base to the outer edge of the bevel gear and write it down, add the two measurements together and that is the amount the top of the pinion need to protrude from the pistol grip.
Fit the motor to the grip with no gearbox in the receiver and use the depth gauge part of you caliper to measure the protrusion of the top of the pinion from the base then adjust until it matches the measurement from before.


@Rattler well it seems simple when you say it that way. Lol. Thanks

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