KJW M9 Gas mag problem...
 

Alright, I have been using Co2 for a month now with no problems at all. Until yesterday my GreenGas mags came in the mail. Filled them with propane. Dropped them in and fired a few rounds...

After the first shot the slide can not go back enough to load another BB... Propane does not give me the kick I need... Any way to fix this?

Using a KJW m9 Elite with KJW Gas mags.

KJW M9 comes in 2 versions - green gas and CO2. It's not just the mags. The frame and most parts are readily interchangeable, but the internals in the gas system in the slide (and possibly some of the springs) are different between the 2 models.

The model CO2 one is designed to allow less gas volume to flow through due to the considerably higher pressures that CO2 exerts compared to green gas / propane. Propane mags won't work as a result because not enough gas volume is being released to cycle the action.

The only way to fix this is to either ditch the green gas mags and get CO2 mags, or replace the appropriate parts to make the gun suitable for propane use. Note that once you do this, using a CO2 mag will more than likely damage or destroy the gun.

There are CO2 capable versions (mostly just a reinforced nozzle) that run just fine on propane, so it may not be that.

I've seen 2 KJW CO2 M9s to date, and neither will cycle with propane mags, exactly as Ryan describes. If not the internals, it may be that it uses different hammer and / or recoil springs to adapt the gun to using CO2's much higher pressure. Either way, they won't cycle with propane mags because of some internal difference to adapt them to run propane without blowing the gun to pieces.

Well... It fixed itself some how... Ran 8 mags through it tonight, not a single misfeed. Maybe the propane I used before was too cold or something... who knows

whouah incredible...sometimes we don't understand. Cool for you!