Thanks guys, I'm not worried about obtaining semi-auto, at least not in this gun, I just don't want BBs to roll out of the barrel do to pressure built up in feeding system or what have you. My feeding system will use a AEG motor driven sprocket to shuttle BBs into a channel and then into a tube or s...

I could not locate that thread jacksmirkingrevenge posted but I did see this on McMaster-Carr. http://www.mcmaster.com/#spring-plungers/=3ntxn7 Its an spring plunder in the form of a set screw. I could use this and still get a air-tight seal in my chamber. I could install this with a bushing.

Thanks bud. I like that hop-up design, it looks like a Sun Project HU sleeve. The o-ring detent is a good idea too. Thanks for the notes.

When you make these HU sleeves are you using these directly on the surface of the projectile or is there an additional material used, like a bucking?

Hello guys, first time poster. CO2/HPA airsoft user. I would like to make a BBMG. I like the vortex block design but they have their drawbacks. Let me know if this is just wishful thinking. I would like to use an air tight sprocket driven BB hopper similar to the P3 M134a auto-loader and feed it dir...