The "Grand-Daddy" of metallic cartriges back in the Days of the Old West was not the "Colt 45" but rather the little known "44 Henry Flat".
The 44 Henry flat was developed back in 1860, together with the 1860 Henry rifle. And so through the Days of the Federal Conquest of the States, and then throughout the Early Days of the Old West, if you were gonna be shootn' ctgs. it was most likely the 44Henry that you'd been using.
The stubbly little rimfire cartrige was normally loaded with 28 grs of black powder and a 200 grs lead bullet. It was a true .44 with a bullet diameter of 446-inch and a case length of .875-inch. The magazine tube of the Henry rifle held 15 rounds. Later, the Winchester '66 rifles and carbines were also made to use the same 44 Henry ammo.
Later, Colt made the 1872 Open Top and about 1,800 Peacemakers in the 44 Henry, and S&W produced a special rimfire version of their big No. 3 breaktop for the Turks. The same ammo was used in both rifle and revolver,- the first use of the same ammo for both rifle and for pistol.
While the 44 Henry was not a potent cartridge, it was, nonetheless a good compromise between size and power. Thousands of guns were made for this cartridge and the ammunition companies loaded ammo for it as late as 1929.
The Henry a rimfire 44 caliber round that gave from a 20 inch rifle barrel, about what today's standard 158 grain lead 38 Special gives in power out of a six inch handgun. The Henry 44 'Flat' as it is know looks like a goiterized 22 RF short.
This guy had a few
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