I wonder if there ever was a moderately powered true rifle round that would have satisfied infantry needs and still be with us today, economics and tradition aside.
Seeing as it'd be wood & steel, and not very modular given the requirements of the day, I'd doubt it. Closest thing to 'modular' then was the MG15, and the only guns of similar construction to WWII methods still kicking are probably the M1A and MP5 (still roughly-roughly similar to the MP44)
Would a .276 Pedersen or .280 British EM still be GI or would the push down to varmint calibers still have taken control? I doubt there are many Russian or Chicom enthusiasts debating the subject, but their Army brass still went smallbore in our wake.
Interesting question, since the difference doesn't seem enough to go UP to 276/280 calibers today. Were we sitting on fifty-years' infrastructure of 280 or whatever, I think there would be at least equal resistance to going 5.56. The Chinese and Russians went even smaller than we did (the Chinese are like 17cal IIRC for several cartridges), but the Russians also more thoroughly developed larger bore offerings like 9x39 and 9x21 for short barrel or suppressor use. The Americans by comparison have been resolute in opposition to any efforts to optimize the bore of our now much-shorter M4s, which is ironic given the slavish dedication to optimization in the M16 (i.e. the variables have changed, but we've been pretending the answer remains the same)
Nowadays, there are a lot of supporters of 6.5mm rifles for more power than .223 and less weight and recoil than .308. (But recall the Japanese and Italians trying to get away from that small a caliber early in WWII.)
I will only say that a long 22 caliber simple FMJ bullet like those nations were fielding would probably perform even more poorly. The tumbling, fragmenting, VLD, and penetrator effects of modern 5.56 and other options have greatly expanded their performance, and we know with hunting & varmint bullets that the same benefits are see in larger calibers as well.
Include the whole 6 to 7mm gang and it is clear where we armchair ballisticians thing the world ought to be going. Which reprises a lot of earlier thought.
It really is funny how clear the math has been all along. A lot of people refuse to believe this, and are astonished at how close to optimal the very first generation of smokeless spitzer bullet cartridges were. I think they simply were able to approach the topic unbiased, and came to the conclusions we're nearing once again. 7mm Mauser was
very close to what we expect from even a modern rifle cartridge considering it was *first*, and 7.5x55 Swiss an even closer refinement (namely with regards to autoloading function)
The 'new' variable we have today is the advent of the "carbine" or short rifle, which had pretty much fallen from favor when lever actions were abandoned for the new shoot-over-the-horizon smokeless wonder bolt rifles and machineguns at the turn of the century. Just as with the old mounted cavalry, we've returned once more to high-mobility tactics, and found that small/light/short is the order of the day. Black powder carbines tended to shoot wide-for-power cartridges, since a fat short bore approaches the volume of a long skinny bore, and bore volume is directly related to how much power can be derived from a cartridge. Since our M4 barrel is more than 1/4 shorter than originally intended, it makes a lot sense to "bore" the motor since we "de-stroked" it, so long as doing so doesn't impact function or use (recoil from longer/heavier bullets needed to maintain trajectory)
7mm, 7mm, 7.5x55, 308, 5.56
Look at this and tell me that we could possibly have significantly more design insight into the problem than they did in 1892
TCB
