Originally Posted by scurvythepirate
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
i have the mp5 a4.
i would like to go to about 350 fps, i am a begginer and want the easiest and safest way to mod my gun without causing damage to it.