I can't tell you much about these, but it does look like they were produced by the Union Metallic Cartridge Company.

They may be caliber .44 Smith & Wesson American for the New Model Army or no 3 revolver.

Or maybe some other caliber with Smith & Wesson in it like .38 Smith & Wesson, but I am not sure.

Hopefully some experts will be by soon.

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My sgntr is mor thn 30 chrctrs