Ignire

Most pistol mags have a gas fill at the bottom just fill that up and pull the spring all the way down to fill the mag with bbs, some mags have a latch that allows you hold the spring down and others you have to hold manually, ive always gone with filling the mag in 3 second intervals, so shake your gas canister, fill the mag for 3 ish seconds and repeat 3-5 times or until you think its full. Hope this helps.