GMT M125 Spring

This is a M125 spring made by GMT. It should do about 430 fps but this could be way off depending on your gun. This is a dual stage spring, which means the coils get farther and close together in different parts of the spring. This is the way all aftermarket springs are while stock springs are constant rate. It changes how much force the spring applies at different points in the stroke. The velocity of this spring makes it best for long range assault rifles.

Features:
- About 430 FPS
- Best for long range assault rifles not meant to be used as a DMR