Stuff is 7.62 x 51 Cavim. Has so much asphaltum "sealer" that it will lock up the HK in 2-3 rounds. Switching to WCC or R-P commercial ammo and firing 2-3 rounds wil "clear" the bore of the sealer, then will fire 2-3 of the Cavim again.
Good brass, so just need to remove the gunk and brighten it up a bit.
Several thousand rounds, so vibrating/tumbling doesn't seem to be a viable option.
thanks