A guy that works for me brought in his family heirloom. An 1878 Springfield Trapdoor, he had the bayonet and scabbard. He also had a leather ammo pouch with some spent brass. The brass is headstamped .45/70. He had a modern .45/70 round that he said would not chamber in the rifle. When I compared his old brass to the newer round I found the spent old brass was about a 1/2 inch shorter than the newer round. The case mouth was also a smaller diameter, usually a spent cartridge is wider after it is fired this one was smaller than the newer .45 bullet. If anyone that can help us out I would appreciate it. I would like to shoot this rifle.