Gasses you can use

[SSMercury]

Uh, Doc, Nitrogen isn't a noble gas. It's an inert and reactionless gas in the atmosphere under normal conditions, but it's not a noble gas in terms of chemistry.

Anyways, you and everyone else is right for reasons not to use oxygen. Helium actually wouldn't be a good gas to use, and neither would Hydrogen. These flow too fast, and in hydrogen's case, it is ungodly flammable. Xenon either, it would flow too slowly. Argon wouldn't be too hot, but would probably be useable. Neon would be your best bet. Or some ultralight organic compound? I think someone mentioned some sort of freon gas that doesn't hurt the ozone layer in Deep Blue for this.

[timag]

who here took chemistry 101?

Pure Oxygen is pretty unstable, so unless you want velocity in the +/- 65 range, i'd stick with HPA. Just buy a scuba tank.

[LittleJP]

Chem 110...advanced chem...got an A

haha imagine putting hydrogen in your tank for a second.

[BajaBoy]

hey if all u hpa useres out there were to all put your money 2gether.. u can rent a tank (well no..) what u do is u buy the air by a gallon.. such as propain.. ox. n2.... look in the phone book.. b-c in Pa at my dads warhouse.. we use 2 play there alot.. and he usen.. um.. propain.. and i think n2 now.. not sure but he use 2 get co2 for us.. its very cheap.. but u gotta pay every month 4 it.. or u thik u might be able 2 buy a compresser.. at www.paintballinc.com (its a booster 4 a normal compressor tho)