Airsoft A&K M249 Hop upgrade (Bullgear hop chamber) and gearbox service

Upgrading my A&K M249 hop chamber to the far superior bullgear hop chamber, also servicing the gearbox to make sure everything is perfect. I used a maple leaf macron 50 degree hop rubber with omega nub in this build. It is set up to run on 0.32g BBs.

Background music:

Max Brhon - Cyberpunk [NCS Release]
Music provided by NoCopyrightSounds
Free Download/Stream: http://ncs.io/Cyberpunk
Watch: http://youtu.be/iqoNoU-rm14