Shotgun borescope
 

Does anyone have a recommendation for what borescope wooks good on your shotguns? Will the ones made for rifles have problems focusing while being used in a shotgun barrel?

I have a BSA boresighting scope kit and the shotgun arbor for it is a tapered one that you tighten to expand to fit the muzzle tightly. The few times I have used it for a shotgun it seems to work well enough.