I inadvertently decapped and re-sized some of my 44-40 brass in my 45 colt die. Could this be bad?
Crossdraw
Frankly, Pard, I don't think you actually did anything more than decapping the .44-40 brass. The base diameter of the .45 LC is slightly larger than that of the .44-40. Doubt the sides of the .45 LC die even touched the .44-40 brass. So about all you did was decap the brass. (Just don't get a .45 LC in a .44-40 rifle, especially a Henry or '66. Takes about 15-20 minutes to remove the larger round from those rifles. A '73 Winchester can be cleared by unscrewing the side-panel screw. See: Texas Ranger George Lloyd's fight with some Indians! He did survive.