Originally Posted by Darklen
Originally Posted by MadMax
It drives me to distraction when I think that the GB Tech gas grenade/reservoirs have the same junky single port valve. Neat looking gas reservoir disguised as a distraction device, but the thing has been made useless with the single port valve. I can't get more than 10g of propane into it without freezing the thing. A doublestack WA mag holds 8g of propane so you can see how crippled this product is.
Intresting service note. I just took a fubared TM glock mag and swapped the valve in my GB Tech grenade. I filled with propane for ten seconds and it isn't even half full yet! Thanks for the heads up Carl!
I should have prefaced my valve replacement comment with a stern warning:
WARNING: the GBTech grenade is missing the stub tube feature normally present in Japanese magazine bases. The tube I'm referring to is the largish (~7mm) dia tube which is part of the mag base (not the valve). This is an overflow tube which assures that the mag cannot be filled solid with propane. This is a NECESSARY feature as it's possible to fill a GBTech grenade completely with liquid (no gas space). This risks explosion of the grenade is warmed somewhat as the liquid has no space to expand into and may rupture the sides of your reservoir. If you do replace your fill valve, be sure to leave a generous gas space. You should feel liquid sloshing in the reservoir like it's not more than 1/2 full, preferably less.
I am considering making replacement bases with overflow tubes for the GBTech grenade/reservoir, but I'm not sure I'll be able to meet the quantities to justify a machining run.