[Mist3r.B]

Here's what I've put in my Kart M-14.

-Guarder 6.04 TB Barrel
-Systema M120 spring
-KA metal Bushing
-Guarder Hi troque motor.

All this to shoot around 365. However, I suspect the cylinder to leak air. M120 should shoot around 400 fps on a normal setup.

so:

1) m140 will probably be higher than 400
2) short AK type
3) I suggest changing the motor for a high torque (Will alkso give you faster responfd on semi automatic.
4)Don't see the need to switch gear if you plan to use it in semi automatic only.