Yeah, Al, I guessed as much - you're just baiting me - and it weren't fair . . 'cause ya knew it wouldn't take much! ;)

Seriously, I think it would be interesting and informative for folks to read (re-read) the articles regarding EXPANSION Ratio and EFFECTIVE Expansion ratio, by John Dustin, which appeared in the May & June 2003 issues of PRECISION SHOOTING.

Without doing any number crunching, it becomes readily apparent that the typical 30 Caliber HBR capacity cartridge is at least AS efficient as the 6PPC – in my opinion, this explains why a well tuned HBR rig stays tuned. AND further, why the .30BR, by any comparison, is INCREDIBLY efficient and such a steady performer. So, the equation becomes matching the “correct” case capacity, bullet weight (I added that to the equation – more later), bulk density, AND burning rate to obtain the desired result.

All single based smokeless powders store the SAME energy per grain; only the burning rate varies – burning rate is controlled by particle size (surface area), deterrent coatings, etc. When one considers 30 caliber cartridges from the BR through the typical HBR capacities (roughly 37.0 – 50 grains of water), the transfer of the energy stored in the powder to energy stored in the bullet (as measure by Ft. /Lb.), the efficiency is startling indeed! This (again, my opinion) helps explain the difficulty in keeping a similarly sized 6mm cartridge in tune; inefficiency comes into play. Though we are blessed with a wider variety of burning rates than we were say, ten years ago, a HBR capacity 6mm , by virtue of relatively poor expansion ratio, is a lesson in frustration – very difficult to KEEP one working. I’m not going to take much more time on this concept – just trying to get people thinking and discussing the topic. However, I believe that there IS a relationship (albeit, as yet undefined) between EFFECIENCY and PRECISION.

Consider that via the BR capacity, one can, with 125 Gr. and lighter bullets, obtain MVs (thus energy) FULLY EQUAL to those obtainable via the larger HBR capacities and bullets of equal weight – this while burning 7.5-10.0 grains less (albeit faster burning) powder – now THAT is efficiency! However, this still does NOT anoint the BR capacity as being the ultimate for thirty caliber. . . THAT is yet to be determined. And NOT, as BR shooters are prone to do, by a sample of one.

One more thought regarding the horizontal/vertical wind deflection of various thirty caliber cartridges: assuming an equal twist rate, bullet weight/profile, and muzzle velocity, once the bullets are free of the barrel, all should behave the SAME – the bullet cannot identify whether the velocity(energy) was imparted by a 42.5 grain charge weight, or a mere 34.8 Gr. For the most part, reports [from various individuals who have several seasons experience with 17/18” twist thirty caliber barrels] amount to rave reviews – and winning results in registered (IBS/NBRSA) tournaments – this makes me tend to believe that the occasional weird result/experience is likely a tuning issue with a INDIVIDUAL barrel. I’ll restate the example of Joe Entrekin – as I recall from our correspondence, once Joe found the “REAL” sweet spot, the two hundred yard “shot from hell” (“out the bottom”) went away. AS pointed out by Ron Baldner, some of us have been shooting these JUST RIGHT twist-rate barrels (1:17” or 1:18”, using bullets based upon 1.00” long OR shorter jackets) in our HBR rigs for more than five seasons with virtually no reports of ‘excessive’ vertical – AND, for the most part, we are obtaining the same velocities via the BR! How could a change in cartridge configuration/capacity affect external ballistic performance?

Having messed with this stuff for a while, I have formulated some strong opinions regarding case configuration: so long as CAPACITY and bore diameter are equal, SHAPE (case diameter, body taper, shoulder angle, neck length, etc.) doesn’t amount to much! For evidence, I’d point to the MANY more or less REGIONALIZED HBR configurations/capacities, which are perfectly capable of winning ( and which HAVE won) at the highest levels – they range from a plain-Jane .30/30 through the full capacity .308 Win. And all of its descendants, including the WareWolf! ;)

Please do not take offense at any of the opinions I have expressed – they are not directed at any specific comment or individual – rather, they're simply my opinions and are made in hopes of generating a reasonable discussion . . . Keep ‘em ON the X! R.G.