I'll add my two pence,
I have a G&G l85 Afv, I've managed to get it to play nice with a Maxx hop with internal tracer and a nanohard (warfet is better but I'm cheap) mosfet useing an 11.1v (do not use without a mosfet) I forget the capacity but it's large.
This has required rewiring her myself.
Its very common to disable the blowback as its underwhelming and will just fail anyways.
Some l85s can be quite picky when it come to mags, I recommend NUPROL STANAG 30/140rnd Adjustable Mid-Caps.
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