Here is a good bc 160gr bullet http://matrixballistics.com/.264-Caliber-rifle-bullets.html
also if want a good hunting bullet the 160gr Woodleigh PPSN is a good performer and I have pushed it to 3261fps with my 264WM with 73gr of H570 with a 30 inch Shilen barrel with
1 in 8 twist. It does show signs of pressure.
http://www.woodleighbullets.com.au/bullet-lists/traditional/264q-333q