Harv,
I'm certainly no expert at ballistics, but for a given FORM or shape of bullet, BC is proportional to weight, ergo, find one that has a published BC and increase it at the same ratio as the weight goes up. There are several computer programs available that will give you an idea about potential velocity(quickload or loadfromadisk), but one of the issues you'll have to deal with is twist rate and that bullet would require a pretty quick twist rate, certainly faster than 1:9. you might find some help at cybermesa.com about that. All in all I think many of the pioneers here at LRH have paved ground ahead of you and you can save a lot of money by following in their steps. JMHO