Ok. I have called everyone and everywhere about reboring my 45/70 trapdoor barrel to either 28ga or 20ga. The gun was acquired already sporterized so keeping it original I don’t care about. Know one seems to have the tooling. I know on a whim you can shoot 410 in a 45/70 but they say the brass expands badly. So here’s my theory, can I put a thin piece of brass tube around the 410 base to take up some circumference so that it fits the chamber better? Will it be safe if I load 1/3” less 410 spec loads? Yes I want to make it some kind of shotgun. I want to use what I have. I know all about the poor patterning. Any ideas? I contacted jes reboring. They can bore to about whatever but the have no means to Shotgun chamber reamers. What says the hive. Thank you all?