Like JB noted, it's not that hard to keep the proper relationship, bore with bayonet. I check before each shot. You can use a cleaning rod, but after a while you learn to "eyeball" it close enough to get a reading without blasting the divice. The more the gun kicks, the more adjustment, getting the barrel back in the right position and in right relationship with the bayonet. It's really easier than it sounds, especially after doing it a while.
DF
