Iosso is so-so. It's not as effective on copper as JB or the chemical solvents. As for it turning black in your barrel, try rubbing a bit on a piece of polished steel. It will turn black too.

There's a few threads that mention it here. The correct spelling is iosso.

Bye
Jack

 

The correct spelling is iosso

Oh, it's an i, not a l... no wonder that I could not find much info...

As for it turning black in your barrel, try rubbing a bit on a piece of polished steel. It will turn black too.

So, you're confirming my thoughts that it's more a metal polish (or grinding paste) than anything else ? If so, am I correct in assuming that it will damage the rifling if used often?

Hennie

 

I think you'd wear out your arm before your barrel, as it seems milder than J-B Compound. The late Merrill Martin, noted benchrest experimenter, thought it was safe for his benchrest barrels. It seems to have some sort of chemical action on copper, as well as an abrasive action. There's no ammonia smell though. One thing I noticed is that it seems to coat the barrel and Hoppes Benchrest won't cut copper through it, so patch out the Iosso with penetrating oil or alcohol. It's been a while, but I think both of them work.

I was using it on a barrel that was copper fouling very heavily, and gave up on it. Firelapping fixed the barrel, and I should try it again. Still have half the tube left.

Bye
Jack

 

Thanks Jack.

Guess that I will save it for the occasional "super" cleaning - so it's back to the Hoppes and Robla for my regular use...

Hennie

 

I have been using the Iosso paste cleaner for some time now. I like it very much. It is mildly abrasive, though less so than JB bore paste. In my experience, it is safe to use all of the time. The black you see on the patches will occur even if the bore (appears) spotlessly clean. This is caused by a chemical reaction with the cleaner...removing the surface oxidation on the steel. Steel will oxidize (very lightly, on the surface) within a few seconds after cleaning...as soon as it's exposed to air. The Iosso removes this. Is this a big issue ? No, it's not....but that's the explanation for the black patches. You may have also noticed a heavy, metallic smell, while using the Iosso. This is due to the same chemical reaction.

As a cleaner, IMO, the Iosso does a great job. Just like with any bore cleaner, if a barrel is heavily metal fouled (copper, lead, etc.), then it will take several applications for the fouling to be removed.

My cleaning routine is as follows : First, I use Hoppes to get out the powder residue. Once that is mostly gone, I switch to the Iosso. Two or three patches does it. Then, I use a heavily oiled patch, followed by a very lightly oiled patch...last. This ensures that the Iosso is out of the barrel....and that the barrel is lightly oiled. By using the Iosso on a regular basis, I have been able to ensure no buildup of metal (copper) fouling.

I highly recommend the stuff. I doubt that it has any long-term destructive effects on the barrel steel. We shall see, in any case....as I use it quite regularly.