Depending on the platform you are intending to place the system into... With some professional machining of the upper receiver, you can transfer the system to another receiver. I have seen some people machine the upper of a VFC 416 and were successful. You will not lose the spring release by transferring the gearbox to another system.
I took the spring release system out of my gun, as the ASCU completes a full cycle and stops the sector gear in the same place, so that it does not interfere with then piston. That is the spring releases main function with this gun, it releases the gears so that you can open and close the receiver without the gears or piston/cylinder being damaged.
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