Alan, I was about to tell Gary I found that out tonight. On the 2nd, when Semmes was mortally wounded, the cavalry was about five miles northeast of the main lines, battling Hampton and Stuart. Elon Fansworth's charge took place the next day, on the 3rd. Farnsworth was killed in the charge. Though he was shot five times in the chest, a rumor went around that he had commited suicide rather than be captured.
Buford's cavalry had passed through the area on the way to start the ball northwest of the town. It's possible someone who did fight in the wheatfield on the 2nd had picked up a Spencer. Could any of the Maine or other units have been armed with them? Sorry this trail didn't pan out. Stan