Thanks for the advice guys,
FC/Rock - This would be a one time thing as I 99.9% of the time use my 300 WTHBY, and time is of the essence, so I unfortunately don't have the time to buy a rifled barrel or test loads. Typically wouldn't even think about hunting this area, but I have an opportunity on a once in a lifetime blackie..... Let's just say DBL drop tynes are involved.
Bobcat - Thanks, I will try to get within that range as I have only the front bead!