Q: I read with interest, your reply to a reader about the 4.85 mm cartridge the British entered into the 1970’s NATO ammunition trials. By my reckoning 4.85mm is .19 calibre, so I am interested in finding out whether or not there were ever any .19 calibre wildcats developed in the U.S? If so, what were they and what cases were they based on?
A: An American experimmenter James Leahy, well known for his Calhoon bullets, recognized the advantages of the .19 calibre. He saw that it offered superior sectional density with ballistic coefficents similar to the .22 calibres. Other advantages were velocities which approached the .220 Swift with far less powder, longer barrel life and less recoil. He whumped up a trio of wildcats; the .19 Calhoon is a .22 Hornet case necked down, blown out to have a 30 degree shoulder and minimum body taper. This little wildcat will spit out a 27gn bullet at 3600fps. The 19 Badger which is based on the .30 Carbine case drives a 27gn bullet at 3730fps and a 32gn bullet at 3550fps; the 19/223 Calhoon is a real screamer, driving a 32gn bullet at 4100fps, and a 44gn bullet at 3600fps. Leahy didn’t invent the .19 calibre but he saw a chance to fill a small gap in the cartridge picket fence and developed those wildcats to fill the niche.