Randy, John Dustin's article is a good one, that's for sure. I've long thought that one of the reason for the benchrest .30's (whatever mutation...30BR, 30X47, 30 WareWolf, et al) have an initial pressure rise that is, for lack of proper terminology....smooth.

   It would be interesting to chart the change in pressure as the bullet moves up the barrel, say at every .050 of travel, for different bore diameters using the same case (a BR case in 22BR, 6BR, 30BR for example).

    Here's another thing that has puzzled me...comparing the 6PPC to the 30BR, there is a huge difference in the case/bore/bullet weight ratios of the two in competitve BR trim. Given the 30BR's (I'll include most other benchrest .30's here as well) propensity for hanging on to a tuneup, could it be that the 6PPC, in it's present form, is still too big given the .243 bore?

  Leaving the issue of velocity needed to be competitive in todays BR world aside, is a shortened 6PPC the real answer to efficiency in 6mm BR case?

  And since any efforts with the 30PPC haven't been exactly Earth shaking, this makes me believe even more in the concept of the accepted 6PPC not being the ultimate...if the 30PPC case capacity is just a bit too small, doesn't that point to the same case being used with a 6MM bullet as being too big?

   Great discussion...this is getting intersting! But I'm off to help my bride make the stuffing for the birds. And to ponder ballistics.   -Al