Hey guys this is my first post on here. I've reloaded 5.56, 45, and 12 gauge. However 458 socom is a new beast. I would like to use my alliant unique powder with some rainier 350gr bullets rated at 1500fps. The 458 has a max pressure rating of 35k and unique has a tendency of high pressures (from what I've read, I've only gone by reloading book data for 12 gauge and 45, never experimented). Anyone have some recommendations on starting weight for the powder? And a possible oal if you've used this bullet. Black Butterfly (458 socom ammo distributer) uses this bullet for their plinking ammo. All the help I can get would be great considering the lack of info there is for this particular set up.
https://www.midwayusa.com/product/10...ated-flat-nose