Originally Posted by Kozzie
KJW pistols shoot under 350 using Propane. Most retailers crono them on CO2 to get them shooting legal to sell.
Yes - definite difference between the CO2, and the green-gas/propane mags. I just picked up a new KJW M9 full metal, it came with the CO2 mag which happened to be leaking out of the box. I didn't shed a tear when i exchanged it for a green-gas/propane mag to resolve the issue. I don't need a pistol shooting as hot as my rifle.
My Cansoft KJW M9 shot 345fps on a fresh mag of propane - this FM KJW M9 shoots 330fps on the same mags.