Revolvers ftw
No, however the gas lasts shorter.
a gas or spring powered one. never electric, electric powered pistols SUCK. i would suggest a green gas luger if your looking for power, or maybe a green gas desert eagle. those are good airsoft pistols.
Varies by the pistol. Normaly better than spring.
if its spring pistol get a new spring or a better piston (if they even make upgraded pistons for pistols) if its gas i cant help you
Electric pistols are not powerful. If you want power, I would recommend a green gas pistol.
Yes. Gas revolvers are semi automatic, there are some spring pistols that must be re-cocked after each shot.
Signaling
If you go on Airsplat.com you can view the prices of green gas. if you want propane, you'll need a propane adapter and you can get propane tanks from sporting good stores.
helium is used in gas ballons .it is the lighter gas
On certain pistols and rifles, yes. You'd need to see if you can buy C02 mags for the certain gun you have.
Helium is a gas and is not found in the body