That is a straight sided round. If the head is the same diameter as the rim, then the case has only .003" taper per side. An Ackley Improved case has a .0075" to .008" taper, normally, taking printed case dimensions of .469" and .454".

.003" taper is even less than my custom bored .375/06 IMP - at .005" taper(.470" - .460").

That .528" shoulder and 35degree shoulder angle is amazing.

What wonderful .338's through .416's it would make, or even a .458.(there are already too many 7mm's and .30's out there)