Ok so this might be pretty long. I have had a KSC glock 19 forever. I love it I even have used it as a primary in woodland (dense woods) and gotten 5-1 kd ratio.
I currently run 3 mags for it, a standard g19 mag, a g17 longer mag, and the extended 50 rd (or 30 if were getting real) mag.
The g17 mag has always been weird from day one. The g19 mag has run alright most the time. The 50 rd mag has been outstanding. Has the best power and way best gas efficiency, i can get 90 quality shots off in a row in a 4 sec green gas fill.
The g17 mag has had off and on (mostly on) cycling problems. The slide will have to be manually cocked before each shot, or the slide will half cycle, almost like a crappy short stroke (i have short stroked the gun, but got rid of it)
The G19 mag will get off eh, like 5-10 really good shots, like very good shots then just go from like 350 fps shot to 0. Like next round its from amazing to 0 gas in mag.
I have taken apart both, cleaned, lubed, EVERYTHING to both, even made the g17 flow valve into a high flow valve (somehow this didnt effect it at all)
The filling of gas into these mags is unusual, i do 4 sec fills normally, then like 1-3 of those depending on the mag etc. The 19&17 mags will sound very quiet at first. Then next 4 sec fill theres no noise at all.
I replaced the o-rings on valves and this slightly helped but not much. Then i took the fill valve from 50 rd mag and put it in g19 mag, i got off 33 pretty good shots on 10 secs of filling.
This was not the case for the g17 mag, still doesnt cycle at all and runs out of gas in like 15 non cycling shots.
Also, when they did work and i was using the glock as my secondary, if the mags sat un- attended for about 30 min to like an hour, when i went to fire them the gas was almost empty. Not sure if this is normal or not. This is my main concern. Why are they losing gas after sitting for a while. Can this be fixed? Is it normal or what?
Thanks if you read all this. If you can help i would be so gratefull, cheers.