My plastic slide on my KSC USP .45 broke recently so I had to order a replacement. I was using propane (oh me..), so now I have a problem. I need to empty the magazine of the remaining propane before I can fill it with duster, but if I install the new slide and shoot off the remaining gas I risk breaking the slide again. I heard manually thumbing the gas valve on the mag to release gas is a no-no.
What can I do?