I have a barrel with 700+ rounds through it (mostly South African surplus) and I'm wondering when copper fouling starts to become a serious problem.  I have only cleaned this barrel with Breakfree CLP up to this point.

I have read that Sweet's 7.62 is a very strong copper solvent.  I also have some J-B Bore Cleaning Compound, which claims to remove metal fouling - although it sounds like it does this by abrasive action more than chemical action.  Finally, I have some household ammonia around, which I believe is supposed to dissolve copper.  I think the latter two might work, I'm just curious if buying some Sweet's, or some other copper solvent, will make the job that much easier.

Of the options above, which would you pick?  Or go with something totally different?

Both are good choices...Just be sure to (brass) brush the hell out of the bore, as that combined with remover is what will get it out.

First off I would ditch the CLP for a bore cleaner. As you have found out, CLP does nothing for copper. It also leaves teflon in the bore and can play havoc with accuracy until you get it out by shooting it. I would use a standard bore cleaner such as Hoppe's, Shooters Choice, Butch's Bore Shine, etc. before I used CLP. Whatever you do, make sure if you do use Sweets, do NOT also use Shooters Choice. The two together will etch your barrel and it has been proven the two do not do well when used one after the other. If you use a standard bore cleaner that does attack copper, you will not have as hard a time removing it as you will after 700 rounds. Remember too that using any of the aggressive copper cleaners will eat up your bore brush pretty quickly. You might want to try a nylon bore brush with the copper cleaners to avoid this.

My suggestion is to use Hoppes #9 Benchrest Copper Solvent (not to be confused with Hoppes #9 Powder Solvent).  It's not nearly as aggresive as Sweet's and some of the others but it still does an outstanding job.  It might take longer with Hoppes but it will do the job.

I have a vague recollection that there are a couple of different types of ammonia.  I’m not sure household ammonia is the same as is used in bore cleaners.

There is also the issue of the appropriate strength (percentage) for proper bore cleaning.

Personally, I’d definitely stay with something specifically designed for a firearm (especially with a $700 or so firearm!!).

I generally use an abrasive myself.  J-B Bore Paste is good, though I feel Remington Bore Cleaner is a little easier to apply.

A good, relatively foolproof, chemical cleaner is Shooter’s Choice Bore Cleaner on a bronze bristle bore brush.  Just be sure to clean the bore brush afterwards since the bore cleaner will also attack the brush.

If you use Sweets, follow the directions carefully!!  Since it is so strong, you probably want to use a patch, nylon bristle bore brush, or mop to apply it.  It will eat up a bronze bristle bore brush very quickly.

I believe I read here a few monthes ago that if you use an aggressive copper solvent like Sweet's that shooting some isopropyl down the barrel afterwards will neutralize the ammonia. Can anyone else verify this?

Shabo