I have an 1839 contract musket with nipple not wanting to come out. Friend at gun shop will do what ever to remove it. It appears the threads maybe smaller than 5/16. Did some conversations use 1/4 nipple?
Fewer ads. Lots of American Civil War content! JOIN NOW: REGISTER HERE!
No, the U.S. military nipples of that era were standardized. I have seen a small commercial nipple threaded into the remnants of the original military nipple. But, that was only a couple of times in many years of experience!