An idea...

[adrenaline151]

I have an idea and I don't know if it could ever work, but I figured if anyone would know or could build it, they would be here...

My idea is for a BCG that you could put in your upper that would hold a CO2 cartridge(like for a pellet gun), and if you could cover the gas tube somehow so that when you pull the trigger(this is for dry-firing practice) a blast of CO2 would cycle the action and reset the trigger so that you wouldn't have to manually cycle it to fire again... Someone with some paintball tech or something maybe could figure it out? I was also thinking maybe a lighter buffer would have to be in place to reduce the amount of CO2 to get the most out of each cartridge.
Maybe this has already been tried, but I think if you could make it work you could sell a shitload of them. So if one of you guys figures it out I want some credit, dammit.
What do you guys think?

[Stickman]

I think that it would require the use of a BFA to reduce pressure, but I think that its a good idea. I lighter main action spring might be required as well. The military FATS systems and the PRISM system are doing something similar, and PRISM is probably the closest. It uses individual rounds that are pressurized and can be reused, and involves a modified weapon.

[TehLlama]

MadBull 470
WesternArms M4A1 GBB
G&P/WA GBB AR's

There's more, if you're still curious I can hook you up with more information that you probably want.

Both systems would be complete replica guns, with their own magazines, etc. They would accept the exact same accessories (pistol grips, stocks, optics, handguards).
They're a bit pricy, trigger feel is close but not exact, but also fire cheap airsoft BBs (accurately), so it's a bit more than just dry fire practice, and very effective for weapon presentation, and close engagement practice.

There's also the RAP4 paintball markers, but I don't have much experiene with them.