I take the lock off the firearm which needs cleaning , I tear off a strip of old t shirt , tie a knot in the middle , place the knot over the flash hole and clean the firearm with Ballistol moose milk soaked patches , the knot successfully blocks the flash hole and stops the moose milk squirting all over the place. Keep cleaning until the patches no longer pick up grey , dry the bore , oil with Ballistol , then clean and replace the lock , put the gun away muzzle down . 48 or so hours later I run a cleaning patch down the barrel to catch any crud left and re oil with a Lanolin preservative.