I am late posting here - my apologies. I have three Siamese Mauser actions, out of which one is slated for a faux-Rigby style 303. My friend Huvius gifted me a lovely custom 45-70 built with a heavy target barrel as a target rifle, and I am not sure what to do with the two remaining actions. I am thinking about a 50-110 on one and have received some very good advice from a forum member via Facebook. If someone wants to go really big, I guess, 577 2 3/4" should be possible.

My actions will feed 303 and7.62 Mosin without any problems, ass they are. My guess is that a gunsmith could make the 405 work - it is very slightly longer than the Wolf 303 ammo that I have compared 405 rounds to. wasn't the 30-40 Krag developed from the 405 or Vice-versa?