I find it fascinating that so many will decry the .30 carbine as ineffective despite it's near-1,000 lb-ft of energy at just under 2,000 fps, then sing the praises of the Thompson M1 that delivered maybe 400 lb-ft of impact slap, or the German MP40 that sent a 9mm out at maybe 1,400 fps. The M1 Carbine was second ONLY to the M1 Garand in terms of bullet velocity and energy, yet get's no respect, with zillions of outright lies cobbled up over the years to bash it.
The .30 Carbine was a pistol caliber, but it was a POTENT pistol caliber. The 9mm was simply a pistol caliber chambered in a longer barrel - same for the .45 ACP. Neither of the later offered much beyond their pistol purposes, while the .30 Carbine sent a 110 grain slug Zinging out at nearly 2,000 fps for nearly 1,000 fpe! The next time your buddy tells you the lie about the .30 Carbine failing to penetrate Korean, quilted vests, you need to demand PROOF of such tripe, because PROOF already exists in the form of videographic footage of the Carbine round punching through TWO, water-soaked, fully-frozen jackets.
Beyond that, the 5.56 fired from an 11.5" barrel is LIGHT-YEARS BETTER than any 9mm. But you do you and live with what happens next.
I shot my first tactical rifle match, mostly because I had time to shoot it on the same weekend as a service rifle match at the same location. I heard about it last minute, bought a Inland M1 carbine the day before ($125), along with 3 new in the wrap 30 round GI magazines ($15 each) and the only two boxes of .30 Carbine the gun shop had, 50 round boxes of Lake City ball ($5 each). I used 10 rounds to verify zero and function and loaded the other 90 rounds.
That was around the time people started milling the A1 style carry handles off AR-15s and installing weaver rails to mount a scope. At that time tactical rifle shooters were taking AR-15 16" carbines and installing muzzle brakes (I never understood why) and various forms of optics, along with custom triggers, etc.
There were plenty of comments about my antique from the AR-15 shooters, but at the end of the day, I took first place in the battle rifle division with my M1A, second place in the light rifle division with my M1 Carbine (dropping a couple points to the match organizer and his HK 93) and took first place overall. That "antique" M1 Carbine beat every AR-15, AK-47 and SKS in the field across the various stages with targets ranging from 25 yards to 250 yards. It was light, fast handling, reliable, accurate enough, and powerful enough to do the job when in competent hands.
I will however argue the .30 carbine isn't really a pistol round, even though it's been chambered in a few revolvers and pistols.
It derived from the .32 Winchester self loading cartridge designed for the Winchester 1905 (and the M1 Carbine borrowed heavily from the 1905 magazine and trigger housing).
The .30 carbine used a 55 gr lighter weight 110 gr round at a 600 fps faster muzzle velocity from a 10,000 psi higher 40,000 psi maximum average pressure, making it even more of a rifle round.
Despite not having a bottle neck and not getting up in the 2300-2400 psi velocity range there's a strong argument that the .30 carbine was the first intermediate military rifle cartridge.
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As for the .223 Rem / 5.56x45 being light years better than the 9mm , I agree in all respects except:
1) muzzle blast and noise level. The 10" XM-177E1 and 11.5" XM-177E2 were oud even with the moderator. All it did was reduce the moise down to the same level as the 20" M16. Indoors a short barrel AR is deafening, while the smaller volume, 35, 000 psi max 9mm Luger is much quieter unsuppressed, and suppresses much more effectively.
2) Ammunition cost. 9mm loads with plated bullets or FMJs are cheap to shoot.
