Reading up on the m70 264WM it seems the throat is extremely short and the bullets have a double taper. This was done to achieve higher velocities. Sierra's reloading manual suggests having a gunsmith ream the throat out because modern bullets in .264 do not have the double taper.
Any thoughts on this?

I have a pre64 m70 Westerner and it does have a very short throat. With most modern bullets I measuring 3.060-3.100" being .03 off the lands.

Perry

Throaters are like $50 from Dave Manson and you can do it yourself.

I have been pondering this myself. I just completed two .264's for myself and find that the throats require a COAL of about 3.230" @ .010" off the lands, while I have a 3.400" MAG Box. I've wondered if throating will be worth it? I thought of trying to throat one just to see.