Originally Posted by airsoftking
does anyone know what is the most effective and easiest way to upgrade the fps on a jg mp5. the gun i have has a metal gear box but abs casing!!
Which MP5 model is it?
A new spring would work, but you'll need a new spring guide, shims, 7mm metal bearings etc.
What FPS are you going for?
EDIT: Go to Airsoft Parts .ca