The fuze is the typical 21-Second M 1907 powder train time fuze.
I’m afraid that the stamping on the projectile body tells me nothing. Maybe Tony or John will know.
Look at the bottom of the projectile. Does it have a threaded hole in the base?
A Shrapnel projectile is designed to eject it’s entire guts intact. The head has a very fine thread which is designed to strip when the black powder charge is ignited. The fuze, head, ignition tube, diaphragm, and shrapnel balls all depart together. Centrifical force spreads the balls into a pattern while the other parts fall to the ground.
The fuze in your photo looks like it was fired at the Battle of the Little Big Horn. Probably quite valuable.