Copper Fouling Removal
The "Ammonia Solution"
The typical "household ammonia" is only 3 percent and does not work very well as a copper remover. However, to remove copper fouling you can use use straight "strong ammonia" (9 - 10 percent) carried by many janitorial supply houses and hardware stores. My local ACE hardware carries the 10 percent janitorial strength for about $1.50 a quart and it works great straight, followed by a thorough cleaning with Ed's Red. Run a wet patch through the bore and allow to sit for about 5 minutes and proceed as usual. Don't use a brass bore brush or jag! I have seen no scientific proof that the use of ammonia in any strength will harm bores, IF the bore is thoroughly cleaned with bore cleaner after using ammonia to prevent after rust.
If your local ACE hardware store doesn't stock the "10% Janitor's Strength Ammonia," they can order it for you from their master order book. The stock number for the 1 quart size is ACE10183.
If you are worried about its high strength, you can bring it down to the 6 - 8 percent ammonia content of most commercial copper removers by cutting the janitor's strength ammonia with some K1 kerosene or water--try 3.5 to 4 parts 10% ammonia to 1 part water or K1 kerosene. This seems to have little, if any effect, on its copper removal abilities.
Straight 28% ammonia (CAS#7664-41-7) followed by a thorough cleaning with Ed's Red can also be used but 28 percent ammonia may be difficult to get and is VERY strong stuff and potentially aggressive on metal.
Some notes about Ammonia. Ammonia won't harm the rifle's metal, the pH is way down there for even 10% but as you get into stronger solutions (> 10%) the pH becomes basic ( >7 up to 14) and is caustic. The problem comes from ammonia being hygroscopic and folks not cleaning it all out of the bore and the attracted water then causes rusting. [As a test I left a polished mild steel strip in straight 10% ammonia for 48 hours and saw no noticeable corrosion or etching.]
Thanks to Roger Rothschild, Chemist, for this information.
...and an Improvement--"Humpy's White Bore Cleaner"
This modification of the "ammonia solution" thickens the liquid and helps to keep it in the bore for more efficient cleaning. You can if you like omit the 1-part sudsy ammonia
2 parts - 10% ammonia,
1 part - standard household "sudsy" ammonia (optional)
1 part - Ivory liquid dishwashing detergent (It has been reported that "Formula 409" can also be used though the resulting mixture is probably thinner.)
This formula yields about a 6.5 percent ammonia solution. If you omit the sudsy ammonia the solution is about 7.75 percent.
I found this on the 'net, if you try this YOU ARE ON YOUR OWN!!!
http://www.frfrogspad.com/homemade.htm#Copper
