Shell casing ID please

[fyrffytr1]

A friend found this shell casing last week and we are both hoping for an ID. I know it was made by the Union Metallic Cartridge Company but that's about all. The casing is about 1.4"s long, about 54cal necked down to about 44 caliber. The double base is something I have never seen before either.
Some have said the shell misfired, was reloaded and fired a second time but weren't there a few guns that used a double firing pin?

 

[TheCannonballGuy]

There are only three 19th-Century firearms which had a dual firing-pin. They are the .44 Henry Rifle, the Model 1866 Winchester .44 Rifle/Carbine, and the Swiss Vetterli 10.4mm Repeating Rifle (known in the US as a ".41 Swiss").

The cartridges for the .44 Henry and 1866 Winchester were not "necked" ...so your friend's casing is for (and was fired from) the ".41 Swiss" Vetterli.

That being said... the casing he found did not originally have the "double rim" base seen in your photo. That casing has been compressed somehow. Look closely and you'll see a bend in the casing just above the "double rim."

Note: Edited to include a photo of an original Vetterli .41 Swiss cartridge. This one is actually Swiss-made ...note the distinctive Swiss-Cross headstamp marking. Your friend's casing has the very same profile -- except for the "double rim" damage, of course.

 

[nova treasure]

The Vetterli became pretty popular in the U.S so there were several U.S bulletmakers. This one having the Union Metallic Cartridge and merging to Remington with the "U" headstamp would place the age of the bullet around 1885-1911.
there were also a shot shell made for this weapon with the U headstamp
Shotshell meaning, loose shot in the head instead of solid lead.

Bill