Those your powder wisely Grasshoppa. You may want to contact the powder companies and get their advice on powders that will give you the velocity you want and still keep pressures safe (assuming you haven't done so already). According to Hawk Bullets, their thinnest jackets will behave like a BT. Might be worth a try if the Barnes bullets don't work.

I do wish you luck. Keep us posted with progress along the way. This will be interesting. Who know's you may just come up with the next "Wonder Round".