Goodness, there has been so much ink spilled over this subject I can’t even begin to rehearse it all. Here is an interesting recent piece.
In past years I have run several series of tests with commercial and experimental barrel-cleaning media in an effort to take barrels that had been fired back down to base metal, with no carbon or copper fouling as a starting point. A part of the test was to see which medium worked as advertised and which was less effective than expected. The tests were divided into cleaners that relied on chemical action to realize the expected results and cleaners that were abrasive in nature to remove the fouling. The results were verified via bore scopes with magnification to validate the findings.
It was no surprise that we found that some barrels responded to some of the chemical cleaners better than others. This was particularly prevalent with the smoothness of the barrel’s interior surfaces. Match-grade barrels that had been lapped to remove any irregularities or imperfections cleaned down to bare metal without too much effort. Run of-the-mill production barrels fouled earlier and were more difficult to clean almost universally, though there were a few notable exceptions.
Upon examining the barrels that fouled quicker, it was found that microscopic voids and tool marks left from the original manufacturing process were the greatest contributors to lead, copper or carbon fouling. The rougher the barrel’s interior, the quicker it fouls.
Even after cleaning down to bare metal with the abrasive cleaners, some barrels still needed chemical cleaners to remove the fouling embedded in the voids and irregular spots.
After thoroughly cleaning a barrel down to bare metal and removing all perceivable fouling and contamination, a tight-fitting clean patch pushed through the barrel still had a very slight discoloring present due to the vapor-thin residues left by the cleaning agents. This was not really a concern because the bore scope verified the condition of the bore to the satisfaction of the test.
Out of curiosity, we tried a few cleaners that had nothing to do with firearms, but were excellent cleaners that left no smudges or residual film in their intended application. What we found worked to enable a clean patch in and a clean patch out was glass cleaner. It removed everything but the shine after the hard work was done by the chemicals and abrasives.
I am not recommending you use glass cleaner on your Ruger, I’m just stating a finding that may be of interest.
We’ve discussed this before, but it doesn’t appeal to me as prima facie wise to remove everything. I need to be convinced before I believe it.
Microscopic voids, minor erosion, stress corrosion cracking, tooling marks, and the like, are part of the scene. No surface will be free of imperfections.
The very first round after removing all of the copper and lead will refill all of those imperfections with copper and lead. Why continue to beat yourself up over trying to get it all out as if the gun had never been fired?
Anyway, I know that Paul Harrell uses soap and water, others use copper cleaners, others use solvents and still others use odorless mineral spirits (I do on shotguns).
I have never heard of using Windex on the inside of barrels. I’d have to study the effect of ammonia on metals (SS, carbon steel, MoCr, etc.) before I was comfortable with that. At a minimum I’d make sure to remove every last bit of the Windex with solvent and patches, and then oil it, before setting it aside.
Have readers ever used Windex on barrels?