Apparently ".32-20" is a cartridge designation: http://www.earp.com/32.html http://community.webshots.com/photo/1240679/1240821 http://community.webshots.com/photo/1240679/1247196 http://www.sixguns.com/tests/tt3220.htm I suppose in the blues songs it means a pistol appropriate for this cartridge. -- Doug Wilson