For subs I start high a couple grains (but below published max load) and work down. The reason is to avoid a squib load and the problems that come with it.
I have a RCBS taper crimp seating die for one of my 300BLK setups but I keep the crimp backed off and only seat with that die. All my semiauto rifle die setups use the Lee FCD.
Edit: If you're using the new Hornady ELD 208g bullets, they're different from the Amax. I use the Lee 300BLK seating...
I've been using this forum for a while as a resource for info about S&W products, and the members here been a great help.
I thought to at least sign up and say thanks to you all for sharing your experience and knowledge with us internet strangers. Thanks!
I'm a member of the NRA and OFF here...