I always find it amusing when people come up with these ideas...aluminum rods "imbedded" with grit and worrying about it detrimentally wearing the bore. So, sending one after another projectile at 2700-3000FPS+ through the bore, followed by combustion gases of many hundreds of degrees, soot & what not! YEAH...no problem there, but God forbid the aluminum rod imbedded with the invisible "grit of death"! LOL!

Ive used aluminum rods for many years without a second thought. (Or any problems) But now I make my own rods. I happened to get a large quantity of 1/8" Carbon Fiber rods some years back. Then I turn & thread the 8-32 fitting adapters from Delrin composite.