Musica

@TheFull9 interesting I get black gunk of my rails every time I clean them post game day and it's a TM hi-capa stock slide. 

Could be impurities in the gas or dirt in the environment.  GBBs don't inherently create substantial fouling inside themselves when shot the way firearms do.  I mean heck maybe the TM plastic wears away just a tiny bit every game and that accumulates, who knows, I'd suspect the gas or environment first though.

The black is the pot metal the TM frame is made of slowly wearing away.

I do a basic clean of my pistol after every day / outing / event.

Thats if its a clean day, if its wet or muddy then during the day - its amazing the state they get in after a couple of hours, especially if you have trenches!