Originally Posted by Damascus
Sweet's 7.62 and Barnes CR10 are a lot alike, where Sweets is thicker like a gel, and Barnes is thin. The Barnes seems to me a bit more aggressive since the patches come out blue much quicker than the Sweets, but I believe its harsher on barrels, so I only use it on badly fouled bores.
When the Barnes CR10 product first came out, the instructions lacked the warning now placed on the product, about not leaving the product in the bore for longer than 10-15 minutes. In fact, the advertising on the bottles stated is was completely safe and not harmful to the barrel. This was in the day when strong ammonia based cleaners were hitting the market, and it wasn't yet common knowledge (at least to me) that ammonia attracts moisture and will corrode the barrels if left in the bore for any length of time. The higher the ammonia concentration, the more agressive the solution is at removing copper, but the harsher on steel when left in the bore. I'm sure this is the reason that for many years, ammonia based bore cleaning solutions were diluted to lesser ammonia concentrations.
As a consequence of the instructions claiming absolutely safe - will not damage bores in the slightest - I severely corroded the bore on a factory Win M70 7mm Mauser chrome moly barrel. I mean the bore was grown in with corrosion like hoar frost. Surprisingly, the barrel still shoots pretty well. But I had to fire bullets down the bore to scrap away the corrosion. Bronze brushes wouldn't touch it.
My last use of the CR10 product was on a stainless Lilja barrel. I proceeded much more cautiously, but again, despite the instructions stating that the product was completely safe on rifle bores, I observed a slight corrosion film building on the bore surface. Just enough to notice. How's that saying go? Fool me once, shame on you. Fool me twice, shame on me.
This was many years ago. Back in the mid-90s. Just last month I gave that bottle of CR10 to a co-worker, who knows not to leave CR10 in the bore for any length of time, and to flush the product out of the bore after use.
Barnes later included the warning statement which remains on the product to this day, to not leave CR10 product in the bore for any longer than ~15 minutes. The warning came too late for me. The M70 7mm Mauser is now a salt water deer hunting rifle, which I leave down on Kodiak Island. The salt water isn't any more corrosive than Barnes CR10.
Bore Tech Eliminator and Bore Tech CR+2 have never damaged any of my bores, and they clean just as effectively as the potentially damaging ammonia-based copper removing bore cleaners.