[Hectic]

correct, the pressure keeps it liquid, and it escapes as gas due to the lack of a syphon tube on the bottom of the valve, hence why we must invert to transfer liquid, holding it upright would still result in liquid transfer (because the gas would become recomoressed in the mag) but the volume of liquid would be far less, perhaps a few rounds worth, maybe more depending on gas chamber size, ie a gbbr mag would likely produce more shots than a pistol mag. This method works just fine, yes the tank has to be inverted (as stated by the OP) the savings is good if you shoot that many mags, but between my pistol and gbbr i rarely shoot my 8rifle and 2 pistol mags in a day. Proloy get 3 or 4 games out of one coleman tank. Yes this would pay for itself quickly, save on waste and such, likely great for a group of guys to use/pay for together but for solo use a coleman tank is still just easier for most. now if i could find an adapter to refill the coleman tanks from a larger tank, that would be ideal for me, but a cascade fill would likely result in half tye volume (read weight) of propane in a coleman tank, not like pumping it in (like getting yer bbq tank filled at the gas station, or having your propane vehicle filled, the same is true for nitrogen and co2, we can refill them via cascading (connecting a big tank to a small tank, via a hose, open tue valve of the large tank, then the small, let the pressure equalize then close the small, then the large, bleed the hose and disconect. But in a "C" sized cylender, the result is about 1000-1300 psi, a full "C" is in the neighborhood of 2200-2600psi depending on temp. Also it should be noted that it has been illegal for quite some time to fill cylenders in the method, tho it is done in alot of places daily, even big companies like BOC/Linde, but if someone ever got hurt doin it it would he an insureance, WSIB and whoever else shit storm lol.