Action Army 6.03mm AEG Barrel 310mm VSR-10 Parts Will fit in all M4

Will fit in all M4 and rear stocks

FPS is around 390 (varies a bit) w/

Prometheus Hard Cut Off Lever V2 (Version 2)

Below 350 FPS (around 340) w/

Action Army 6.03mm AEG Barrel 310mm VSR-10 Parts Will fit in all M4The Action Army 6. 03mm AEG Barrel 310mm. Fits inside AEGs that require this length. This is a 6. 03 inner barrel diameter, so it allows for less jams and tolerances than the 6. 01mm. A very popular choice as an alternative to the Prometheus. One piece high grade metal machined. Precision smooth inner bore with nickel plating. This inner barrel is an upgrade to improve your gun's performance, accuracy, FPS, and range compared to stock gun barrels.