You can use anyting as a barrel cleaner I guess. And talc might be fine, but it is still an abrasive. Brasso might by OK to get the copper out, but I dont think it works well on carbon and cellulose deposits.

Old bisley shooters I have spoken to used to use brasso as a lapping compound to smooth out rough .303 barrels. I cannot say how well it worked, but at least two people swore by it.

So why is Brasso not a barrel cleaner - Soft Talc and all ?

It's not aggressive enough, or selective enough.

It'll polish whatever is in the bore, not remove it, and also polish the bare metal of the bore.

You may have carbon deposits mixed with copper deposits and it'll polish all equally and remove nothing.

Anything that can polish metal is an abrasive, just of a fine grade. I won't put abrasives of any discription down a barrel. It's softer that the barrel steel or it stays in its box or bottle.

Anything that can polish metal is an abrasive, just of a fine grade. I won't put abrasives of any discription down a barrel. It's softer that the barrel steel or it stays in its box or bottle.

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It was mentioned that it was only abrasive enough to remove oxidation caused by the ammonia ??, in other words merely effectively a brush ? 

Anything that can polish metal is an abrasive, just of a fine grade. I won't put abrasives of any discription down a barrel. It's softer that the barrel steel or it stays in its box or bottle.

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It was mentioned that it was only abrasive enough to remove oxidation caused by the ammonia ??, in other words merely effectively a brush ? 

It contains abrasive like pretty much any other polish. If you rub it up and down inside a barrel it abrades. How much it will abrade is debatable but abrade it will. Copper can be dissolved so on the rare occasions I have had fouling I've used copper solvent and bronze brushes. That worked fine so there is no way I could be persuaded to use an abrasive polish instead.