I've done a couple of articles on this subject, but instead of just stating my opinion interviewed a bunch of people, mostly long-time professionals in the shooting business. The majority of them believed there are inherently accurate cartridges, through their experience with using much more accurate pressure and velocity equipment than available to "home" handloaders, and shooting on indoor ranges.
One was Bob Nosler, who said Nosler used to use the .308 Winchester or .30-06 for the regular testing of lighter-weight .30 caliber bullets, and the .300 Winchester Magnum for testing heavier .30's. (They pull bullets randomly off the production line and shoot them in the indoor range to see if they're meeting accuracy standards.) But after the .300 WSM came out they just started using it for all their .30 caliber bullet testing.
Another was Ron Reiber of Hodgdon. Ron said that the 30-degree shoulder featured in so many "accuracy" cartridges over the decades, from the .219 Wasp (the king of short-range benchrest shooting in the early days) to the PPC cartridges definitely results in more consistent pressures and velocities. It doesn't have to be exactly 30 degrees, as anything from 25 to 35 degrees will also work, but 30 degrees is the center-line for that sort of consistency. He also said a shorter powder column also definitely helps. When Ron develops wildcats for his own shooting, he uses a 30-degree shoulder.
Mule Deer,
Did you once say that Ruger kept records and found the 220 Swift produced tighter groups than the 22-250 rifles they built? I remember this, but I can't find it in writing anywhere.
