Also on JBM
http://www.jbmballistics.com/cgi-bin/jbmstab-5.1.cgi JBM caters to all the manufacturers not in easy drop down tables all the time but the length of the bullets is in the data base. overall JBM has it covered somewhere. Berger caters to their bullets nicely it would be nice if Sierra did the same.
I was talking to a guy that is on the Australian team for target rifle yesterday, and the week before I saw he had a 50 with 10X and even using F Class scoring rings which are smaller he would of had a 60 with 10 x anyway he agreed that slower twist or just enough for a particular bullet is the best.
That makes choosing your barrel a whole lot harder as you are really making it for a specific round, which in target is normally the case as the Throat is even made with reference to a particular bullet.