just a tip in reshimming, do it without the compression parts. Put on the motor and hook up the battery. run the motor while adjusting the motor plate screw at the bottom. You'll have an idea of the sound when your motor is already at its optimum height.
In m4s (v2), after doing the above, you could try to install right half of the mechbox with the pistol grip. Lay the bevel gear, install the motor and screw the motor plate. In this way you could really tell where the motor pinion gear meets with the bevel gear.
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5.56x45mm + m27 = M249(SAW)
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