>I continue to think longer/thinner is not better. Only time will tell. P<

Pete, I believe that time will prove to you that it is a "tasted Great / less Filling" issue - it just doesn't matter.

My experience with the .222s & .2221/2s as compared to  .22 Waldogs (a .22PPC shortened  - roughly .125" short - to be of equal capacity to the .222), would tend to make one believe just the OPPOSITE; that LONGER IS BETTER! However, I do not believe THAT to be a correct conclusion/explanation regarding the relative success of my .222 family chamberings comapred to the short/fat .22 PPC version. THAT was merely a difference in barrels. Perhaps any/all of those barrels would have proven either better, or, worse had they been fit, chambered and cut to different lengths or contours - in my experience, there aren't too many truly "BAD" barrels.

With regard to comapring equal bore diameter, bullet weight and the same powder: I do not believe a human walks the planet who is capable of distinguishing a stastically valid difference between two cartridges of equal capacity.

The emergence of the PPC  was coincidental with a LOT of 'break throughs' in precision shooting/gunsmaithing; chiefly, NECK-TURNING as opposed to reaming. Even when I began competing in BR events [in 1976], outside neck-turning was just gaining wide use - not everyone had a lathe and the hand-held neck-turners were new and expensive (imagine THAT!). But everyone reamed . . . By that time, the 6x47 (.222 Mag. necked up to 6mm) had been bad-mouthed and abandoned by most. I do not believe that particular case ever got a fair shake; by the time neck-turning was the norm, the PPC was the darling . . and the 6x47 was doomed by the myth of being fussy! Now, in my experience, if you want to experience FUSSY, look no further than the PPC! 

The PPC became king because of the simultaneous emergence of chambering / gunsmithing knowledge and case preperation technologies: EVERYTHING got BETTER. But in BR,  only  a few unfortunate words [from the 'right source'] can bring the ruination of a viable platform or componnent; be it barrel, bullet, powder, etc. The REAL trick is ignoring the inane babble and trying stuff out for oneself . . . even then, we run the risk of making value judgements based upon a statistically invalid sample - especially when the sample is 1 - jumping to conclusions is one thing that BR shooters ARE [collectively] good at! ;)

When one peruses an equipment list and notices that 98%+ of the rifles are chambered for one cartridge, even a bloke like me isn't too likely to bet on anything else 'winning' the race! No, the PPC is great because of three things: 1) with the 65-68 Gr. bullet weight,it's about the ideal case capacity for a 6mm; 2) the cases are simple to make; 3) the introduction converged with emergent technology, for which the cartridge got the credit.

>My thinking with regard to Efficiency is related to the fact that you can take the BR case with , say 35 g of 130 and make it go 3000 fps + with some of your light bullets and one needs to use a lot more powder in a longer case with the same diamater to make the same thing happen<

This is exactly the point! It just happens that, in your example, the longer case is less EFFECIENT relative to bore diameter - it has nothing to do with shape/configuration; rather, it is about matching the case volume to the burning rate/bulk density [of the powder] and bore diameter - EXPANSION RATIO. It may be accomplished with either long and skinny, or, short and fat - the [mostly confined] expanding gasses cannot tell the difference.

The ONLY reason we are using the larger capacity cases in Hunter Class rifles is that IT'S dictated by the rules! One can use N-130 in a .30x47 and achieve very respectable results - the drawbacks are that there is a LOT of empty space in the case, thus, it IS easier to exceed safe pressures and ruin cases. The correct answer: Where not regulated by arbitrary case capacity rules, configuring the case capacity to use the fastest burning powder which will completely fill the case, while safely imparting the desired velocity to the desired bullet usually yeilds the best results: i.e., .30BR! (Note: though we were simply not interested in using the "PPC" platform, we did discuss using it rather than the .30BR . . . its smaller capacity may well work wonders if/when combined with, say, N-120, H-110, etc.)

There may well be other concerns which play a bigger role than case configuration - especially case-head diameter, where, in my opinion, due to less thrust (less surface area for the powder gass to push against), the .222 and PPC families have an edge over larger case heads like the .308 and larger. At the same operating pressure, a larger diameter case increases the compressive load on the locking lugs. While here, I will confess to believing that a  relatively straight-walled case wall helps reduce this thrust; however, it contributes nothing else to the equation.

Bottom line. It's a complicated puzzle - it's a miricle that we can get what we do out of our rifles!

Keep 'em ON the X! R.G.