I built a .410 on a Moslin-Nigant action with a Douglass .411 Bore barrel. I have pushed 260 gr bullets to around 1,700 fps. without blowing out the rims on the cases, but any faster an the rims blow out. I built the gun hopeing to use brass cases, which would have been the same as the .405 Win. ( Teddy Rosevelt`s favorit African plains
but Ohio won`t let me use solid brass cases. I did send for tech. data on their ammo, my give it a try.