When I was employeed at a shop near here a few years back the machinist built 2 slug guns as test beds for barrels. He cut and crowned them on the lathe. Used an included 11 degree crown and simply cut it from the outside to the inside. A polishing job and all was well. He had one of them shooting sub 2 inch groups at 200 yards.. I think it was built on an ABolt shotgun action?
