And, I would guess that about 3,800 fps also ! I have personally switcheda fast pass down a rifle barrel will get some of it off.....
I got some walmart pet section walnut and the moly came off great on bullets I molyed myself but factory molyed bullets were rough.I found something by pure accident that may help out.
I sprayed some moly dry lube on a 10/22 action/receiver for use as a dry lube, of course it ran out and dripped on the floor, being the luck I have it was right on wifes side of bed
Tried everything I could get my hands on to begin with, and 99% alcohol wiped it up like it was still wet.
It's worth a try, maybe this will help you out