When I was shooting a lot with the MK IV 22 with a TK brake on it, I would notice it would get clogged up and the dip worked well on both the aluminum and later SS brakes we had. Literally let both of them sit overnight in a bowl of it and never noticed any damage to either. I also sand blasted the aluminum one the first time it got clogged up so it was bare aluminum.
edit to add, I don't let my baffles sit for very long in the dip and rinse with hot water.
As mentioned above the dip is very toxic as the lead is in solution and easily absorbed.
It should not be going down the drain.
