Very few products in this world work exactly as advertised. Slip 2000 Gas Piston Parts and Choke Tube Cleaner sounds too good to be true: non-toxic, biodegradable, doesn’t smell bad, and it’s advertised to remove burnt fouling off gas pistons and choke tubes in only 15 minutes. As the otherwise happy owner of a Beretta 391, I have never been able to get all the crud out of the nooks and crannies of its gas piston, which seems designed specifically to frustrate cleaning. I called Slip 2000.

“No problem. We invented this with the Beretta 391 in mind,” said Slip’s Greg Conner, who sent me a 16 ounce jar ($15.50 from

I dropped my 391 piston into the milky white, citrus-scented goop, pulled it out a quarter of an hour later and with a little brushing, the caked residue flaked off. All of it. For good measure I dunked the piston from an old S&W 1000 with the same results. Then I threw in a ported choke tube caked with powder reside and plastic wad material. Some scrubbing and voila, it was spotless. After that I found myself searching though my choke tubes looking for cruddy ones to clean. I hate to admit this is my idea of big fun, but there it is. If anybody out there has a miracle cleaner they swear by, I’d like to know about it.