I wanted to be able to see down my rifle barrels to check for leading and other things but I couldn’t see spending hundreds of dollars on a good borescope. What I found on Ebay is a cheap 20″ long borescope (microscope) which displays directly to your USB connected computer. (link updated, now $38)
What you get for your $34 is free shipping from Hong Kong, the 20″ long scope with USB connector and light switch, a mini CD with the software, ruler and instructions.
The largest diameter of the scope is at the camera end and it measured out at just .29″. Since this is not a high quality item there may be some variation from sample to sample but I would think it would safely fit a 32 cal and larger.
I ran the scope down the barrel of my 1866 Uberti and was surprised by the condition of the barrel.
I then cleaned the bore with a cleaning brush onto which I wrapped some copper scrubbing pad material. I put enough on so that it was a tight fit in the barrel and did some scrubbing.
After the scrubbing I again took a look.
Here’s a shot of the borescope down the barrel and the view the operator has on his computer.
And lastly I’m pointing the scope at myself so that you can see the LED light which is used to illuminate the path.
All in all a very worthwhile investment of $34 I think.