Hi Jim:
You got great advice from the previous posters!
I have used the products that you mentioned in your post for cleaning rifle barrels. I do not think that they would do any better than steel wool in a shotgun bore!
For cleaning shot guns, I use a mix of ATF and acetone. This is also the best penetrating oil that I have ever used.
One could play with mixing different solvents with the ATF and develop a cleaner that would not harm stock finishes and plastic parts like the acetone will.
I also like a spray brake cleaner to clean parts that I can not gain access to easily!
Good luck,
Franchi
