I made one of the electric bore cleaners and they work. I used a low volt hand tool charger I had lying around instead of a battery and a 1/8 steel rod. Tried it on it on some old military rifles I have. These barrels were really gummed up. So I decided what the heck, I used window cleaner with ammonia in it for the bore cleaner, don't want to leave that stuff in a barrel very long. It really got some junk out. Now I have a copper coated steel rod. Then I cleaned the barrels really good with regular bore cleaners and finally with a light coat of light oil. A couple of the barrels now look great and it improved accuarcy. Larry is right, you may not want to find out whats under all that gunk. One old Mosin bore now looks like a gravel road.