Joedog, welcome to the forum.

You have inherited an oldie. That gun is called a Model of 1905, and with that serial number it would be early production. It was probably shipped about 1906, so it is over a century old. I doubt this gun would have been issued to your grandfather unless he is a lot older than I think he could be. He probably picked it up for himself somewhere along the line. Or could he have inherited it from his father or grandfather?

Can you post pictures? You can either add them as attachments to your posts to this forum (use the "Manage Attachments" button that you see a little lower on the composition page), or just upload your photos to a free photobucket account and put [IMG] links to the photobucket pics in your message.

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David Wilson