Hello all,
I just picked up my Bushmaster 50 and have a few questions.
What about optics, rings, bases?

Cabela's has a package deal, RCBS press, and 3 dies for $529. Seems high but I haven't started shopping yet.

What's a good reloading manual for the .50 BMG?
Any other info would be appreciated.

A great place for 50 cal. info is the Fifty Caliber Shooters Association.

http://www.fcsa.org

Surf over to their site. Full of info on the fifty. I don't think they publish any load data, but just about everything else. I recommend that if you are a 50 cal shooter you join their group. Membership @ $40 a year includes a subscription to a quarterly magazine Very Highpower.
This organization is the front runner in the ongoing fight to keep the 50 BMG legal. FCSA works nationally and state by state. They (we) need all the help they can get!
Food for thought.

muck

Thanks muck,
I will see you there!

Shop around, I got my press for about $100 bucks less.
You can also check out these people for more tools and reloading components.
Wideners