I recently purchased an old schuetzen rifle that came with some interesting notes that probably date back 70 or 80 years.  One note is on case cleaning:

"Clean Shells

Boil in water 1 qt 1 table spoon full of vinegar.  Then put in Cyanide Potassium about the size of a walnut to 1 qt water."

At the time, I believe that potassium cyanide was widely available as rat poison.  What would it bring to the case cleaning process?  Does it neutralize the residue of mercuric priming?   

Doug Nelson

I think I read something of the sort in a letter to the old periodical Shooting and Fishing.  Seems to me the case cleaning formula was by one of the old Scheutzen guys; maybe Eugene Patridge (inventor of the Patridge sight).

I would surmise that the cyanide complexes the oxides or sulfides of copper and zinc that form the tarnish on the cartridge case, without otherwise dissolving the metal itself.  Certainly would work, and back in those more robust days, nobody gave the toxicity a second thought.  Nowadays, you'd need Hazmat training (and approved protective equipment) before anyone would let you try it.

All, thank you for your replies.

FITZ, I'm not at all inclined to try it out-- just curious what the KCN was supposed to do.  Doing pretty well here, and I hope to see you at Roy's Spring match.

Bent_Ramrod, singleshotman, from your comments the cleaning process doesn't sound quite as crazy as I thought.  Still, it's not something that I'm going to try!

Doug Nelson