They didn't take any which was fortunate for the cavalry troopers. There is good reason why when fighting indians one saved the last bullet for themselves.
A fascinating read is Black Elk Speaks
Black Elk was a member of the Sioux nation who participated in Little Bighorn and describes the battle in his biography. Black Elk died circa 1950.
Here is his biography:
We and everyone else in America knows there were none who survived the massacre.