Well - Many thanks to those who posted. I was given a pile of used brass from Old Ranger, it includes Winchester, Dominion, Federal, large and small print Imperial, and Super Speed. Its interesting to note the tremendous variation in base thickness amongst the various brands.
Its also interesting to note the factory loading for the cartridge, using 150 gr pills, is in the order of 2600 fps, and the original design approached 2800 fps - this cartridge was no slouch! Given the tremendous variation in case volume, the short neck, and the variation in bullet profiles, its easy to see how the reloading recipes are all over the map.
Eagleye - if memory serves, you're shooting a Rem 700. Running the loads up to 308 pressures is easy to contemplate with such a rifle. I've got a 50's vintage 99 and a 760. I'm off the the range today with 40 gr of 4064 under 150 gr SP's (Win cases), and 40 gr of Re15 under 180 RN's (Imperial cases) I'm working up to these loads, of course.
With deer season imminent, it'll be a busy day at the range!