What's the most powerful CO2-powered BB/Pellet gun?
I was thinking about making a BB gun that took a CO2 tank from a paintball gun, and paintball parts. But then I realized that since BBs are so much smaller in diameter than paintballs, then there might not be enough pressure to get good velocity, at least not without a long barrel. I calculated that the area/mass ratio for paintballs is about 1.5 times what it is for a BB, so to a first approximation I can expect to need 1.5 times the pressure to accelerate a BB to the same velocity as a paintball in the same space of barrel. Paintball markers run as low as 2-300PSI, but only shoot 300fps. If I wanted say 650FPS I would need 900PSI which is all you can get from raw CO2.
I know the real powerful pellet guns use a spring piston. I know there are CO2 powered BB guns, but I think they only get 700fps at the most out of using raw CO2, and that's with the long barrel. But then I'm not sure if they intentionally throttle using valve dwell in order to get more shots/cartridge. I'm wondering if I used the highest-flow valves etc that I could, how much velocity could I get out of raw CO2 with a BB?
I figure that using larger BBs doesn't help, because volume scales as R^3 but area scales as R^2.
I was thinking about making a BB gun that took a CO2 tank from a paintball gun, and paintball parts. But then I realized that since BBs are so much smaller in diameter than paintballs, then there might not be enough pressure to get good velocity, at least not without a long barrel. I calculated that the area/mass ratio for paintballs is about 1.5 times what it is for a BB, so to a first approximation I can expect to need 1.5 times the pressure to accelerate a BB to the same velocity as a paintball in the same space of barrel. Paintball markers run as low as 2-300PSI, but only shoot 300fps. If I wanted say 650FPS I would need 900PSI which is all you can get from raw CO2.
I know the real powerful pellet guns use a spring piston. I know there are CO2 powered BB guns, but I think they only get 700fps at the most out of using raw CO2, and that's with the long barrel. But then I'm not sure if they intentionally throttle using valve dwell in order to get more shots/cartridge. I'm wondering if I used the highest-flow valves etc that I could, how much velocity could I get out of raw CO2 with a BB?
I figure that using larger BBs doesn't help, because volume scales as R^3 but area scales as R^2.