You can buy a bottle with a regulator dropping the High pressure to 1000psi.
Getting the bottle to fit the gas tube is the difficult bit. You need a...
CO2 the whole gun will be designed to work at much lower pressure & because of the way the different gasses act (CO2 becoming liquid under pressure)...
Large fishing weights hung with a wire trace on the loop tied to thick fishing line. Attach a weight to the other end, throw over a branch etc. Use a...
And you can get into a "vicious circle scenario", where fierce acceleration creates very quick pressure build up, with higher temperatures and higher...