I am the one with the #1H rechambered to .460 Weatherby. I haven't treid any of the lower loads out of mine but I have seen the data for it so it would be easy to do.
I have been playing with lighter bullets in it though. I am trying a 300 gr JHP that shoudl be going out at 2,900 fps. I am looking for something that shoots a little flatter than the big 500 gr. round nose.
NJW in AZ