Froggie.....congratulations, that is a tough tool to find, especially with the die (seems to get lost a lot and it's the only thing that has the caliber marking).
It's not the hardest Winchester tool to find, but it is right up there at the top. So a good find.
To use the tool, you decap using the decapping pin and a hammer (or rock if you prefer), completely separate from the rest of the tool. Priming is accomplished by placing the case in the hole on the side of the main body and seating it with the pin in the handle. Powder is from a little brass measure (in your case marked "48") and then the wad with the bullet started by hand. Into the die it goes with the rim into the "shell holder" in the bottom of the frame and the top of the die into the threaded handle at the top of the frame. Start turning and it will full length size the case, seat the bullet and crimp it in place all in one operation. It is a PITA to use, but you will be one of the few in the world actually loading with a Winchester 1888 reloading tool.
You need to use a cast bullet from a Winchester mold for the proper length, but unlike the tool, those are plentiful.
I have a set for a 40-82 Winchester in a Hiwall and use it. It will make you appreciate your more modern tools.
(You need to Login or Register to view media files and links) Give it a try, lots of Winchester molds in 38-55 on eBay.
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