There is a very long explanation regarding joule Thompson coefficients of air vs helium but the end result is they aren’t ideal gases and don’t expand the same. In fact for the same volume and pressure of air and helium you will get less work out of the air when you expand it than the helium. So basically faster bullets for the same gas tank specs.Why the "air" gun should run on helium? What are helium advantages over air?
Do you still use helium as propellant, since this may complicate things when bringing rifle to Africa?
(helium compressed cylinder in airplane?)
Didn’t know we had another chem e stalking around here on the forum. Nice to met you sir.Hydrogen should work well...oh wait, wasn't there something about a hindenberg???
Sorry, smart a*^% comment from the Chemical Engineer in the room.