It’s a Gen 9 M4, fitted with a 7.5mm alloy inner barrel 34cm long, aftermarket t piece from M4A1, 1.25 unequal spring, green o ring, 11.1v lipo… stock 18:1 nylon gearing and all original nozzle, cylinder head and piston… nothing wild about that setup.
It will empty a Gen 9 mag issue free with any gel (AKAs, ArmourTech greens, WI reds, milkies… all good).
With the Gen 8 mags all the gels will work for about 10 cycles before blocking up. Gels seem to fill the t piece and push up into the barrel. When it’s jammed if I point the muzzle downward, several gels roll out the barrel ( good name for a wartime ditty ).
Makes no sense to me… I would have thought that if a Gen 8 mag feeds a Gen 8 t piece and barrel setup there’s no reason for it to be incompatible with a Gen 9.
Would it be worth throwing in the old plastic barrel and t piece and running a Gen 8 mag through it? T piece issue is about all I can think of at this point.