The site base appears to be an 1898. Serial number is 77679. I took this carbine with my 1903 Springfield, M1917 Remington and M1 Garand to the range, and wow. I love how smooth the action is. I had never shot one before, and it very forgiving for a guy that is not the best shot..lol Amazing carbine, time to get a rifle next, I am hooked! Thanks :)

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