What do the 223 WSSM and the 50 BMG have in common?

How about the 6mm-06, the 7mm STW, and the 300 Remington Ultra?

The 264 Winchester and the 338-378 Roy?

Most obviously, they will all make urban liberals wet their pants.

But less obvious is that all 7 chamberings have very nearly the same case volume to bore area ratio, of about 5.5:1.

Within the calibers with proper long range big game bullet selection - 264 through 338 - and with a 26-27" barrel, all will put out a .28 SD bullet with a BC in the mid .500s at a touch over 3200 fps or a .25 SD bullet with a BC in the upper .4s at close to 3500.

Full loads give a muzzle energy that is very nearly constant across the range at about 41 foot pounds per grain of case capacity, and just under 60,000 foot pounds per square inch of bore.

Given suitable barrel twists and bullets, it would seem what you can do ballistically with any one of these you could also do with any of the others differing only in scale of terminal effects on the far end. Furthermore, if you shoot any of these calibers, you can accurately describe them as a Mini 50.

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Geeeeeez aspade, and people say I have too much time on my hands! Actually your comparisons, calculations, and conclusions are quite interesting. Thanks!

I'm in the planning stages of putting together an open country huntng rifle. I don't have the shooting skills to get much besides extra noise from going beyond a .270, or probably a .308 for that matter but that isn't the point. I started to read up on high velocity cartridges, but mostly came across ambiguous statements about blast and barrel burning and overboreness, and not many concrete numbers.

So for curiousity's sake, I made up an Excel sheet which takes the bore diameter, case capacity, barrel length, and approximate muzzle energy and outputs a number of ratios which seemed interesting to me.

The 7mm Rem Mag is a bigger 25-06.

The 7mm-08, 30-06, 338 Winnie, and 375 Holland have practically the same expansion ratio and scale linearly in energy developed.

If a 25-06 ought to have a 26" tube, the .257 Roy ought to have a full yard - and if it did it would put out 115s at 3700.

The 7mm RUM is, proportionately, a .30-06 necked to .224.

I've clearly lost sight of what I was originally trying to do, but I've learned something along the way. And I have much less time left on my hands than I did when I started this exercise.