mjobrien10
The gas ones use Co2 cartidges that can be purchased at any wal-mart or paintabll shop. The battery powered ones are semi and fully automatic. Both Battery and Spring only use springs for propulsion of the pellet. They all have about the same power but in my experience the Co2 gas guns have a bit more power. Oh yeah, you must be 18 to buy the gas cartridges. Hope that helps, and don't shoot yer eye out.

sort187
A gas gun uses something called "green gas"....it comes in like an aerosol can...Battery powered takes rechargeable batteries like you'd find in an R.C. car....spring powered....well, that's self explanatory. The gas and the electric are going to be a little more pricey, but usually, with the proper care, well worth the money spent....spring powered is something I personally wouldn't waste my time with....one recock, one shot.....and usually made of cheap plastic....junk. Purchasing the gas....I think you have to be 18 or older to be able to purchase that..... This site should help: Good Luck and Happy Shooting!