What kind of borescope did you get?
I got one that simply plugs in USB port and computer (some cell phones) will recognize it as a camera.
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This consists of a electric cord with a connector on the end. A fibre-optics cable connects to the cord and has a fitting on the end with a 45-degree mirror. This allows you to look directly down on the bore. If you take off this mirror fitting, you can just peek down the bore. I bought the model that had a 48-inch long fibre-optics cable so I could inspect my long rifles.
Here are some sample photos. These are all Black Powder guns.
"Hawk" = .50 caliber Hawken Rifle - 36 years old
"Bed" = .36 caliber Pennsylvania Rifle - 30 years old
"Ruger" = .457 revolver pistol - 48 years old
"Dueling" = .50 caliber dueling pistol---brand new.
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