Modify gears and TM piston
 

How do modify torque gears mesh with a stock TM piston? I have yet to break my piston and the teeth are still in great shape. The spring is only shooting around 350 fps.

Modify gears will work with the Tm piston, but since your going to be opening the shell you might as well replace it with something better,

http://www.airsoftparts.ca/store2/in...oducts_id=1237
or
http://www.airsoftparts.ca/store2/in...oducts_id=1173

these are two of the best cuz of thier price and jugglez will vouch for that.

Good luck
Beach