That non-tumble lube Lee version is a copy of a bullet design by C.E. Harris and moulds were originally produced by the now defunct NEI company. I bought one of the moulds more than twenty-five years ago and used the bullets in a Ruger 7.62x39 bolt-action. I don't know how close the Lee design is to the original, but the NEI bullet shot quite accurately. It does have a fat nose and my notes indicate an OAL of 2.20" with bullets sized to either .311" or .312" - either size did fine in my rifle. Most .30 caliber rifles have groove diameters of .308" and I routinely use .311" cast bullets, with the exception of a Remington .308 that does better with a .310" bullet.
There are always exceptions, but generally, the largest diameter cast bullet that will permit chambering a loaded cartridge without difficulty will be the most accurate for a particular rifle.
