Now those (any really) cut down carbines will.be less accurate from the reduced sight radius, not the shorter barrel.
They were proper production weapons they made 100s of thousands of them.
The M1 and M2 carbines were popular in Viet Nam. I know of several guys in LRRP that preferred them to M16
There has been testing of that with AR-15s, between the 'pistol', carbine and rifle length barrels, and with the same optics, hardly any POI change from 10.5" to 26" lengths, and not as much velocity loss as one might expect, either
I don't doubt the test results, but it just seems counter-intuitive to me. I'd think that minor difference puts an incentive to make more carbines (so long as the cartridge choice is matched to the gun)
To me an AR-15 pistol with 10" barrel and a 'brace' that is totally not a stock, isn't that much smaller than an AR Carbine with 16" barrel and adjustable stock.
One of the suspected causes for the alleged wandering zero was that the lightening cuts made to the No 5 receiver caused it to flex when fired and deform slightly over time. If the No 5 used the .30 carbine round this wouldn't be an issue so the problem wouldn't arise. Mind you there is a strong suspicion that the whole issue was blown vastly out of proportion by the Army to prevent the No 5 being made the new standard rifle when they knew they needed a self loading rifle. Again using the .30 carbine round would prevent that problem as it's not powerful enough to be the main service round.
The M1 Carbine used a strong pistol round and a detachable magazine while the SKS used a weak rifle round and a fixed magazine. Both are comparable weapons, both were produced by the million and used for many years around the world. That they were replaced by later weapons does not make them failures.
www.battleorder.org
That's not proving it a failure, as the Carbine was meant to take the place of Rifles for certain roles, as previous the M1911 pistol was shown to not be an effective weapon for ammo carriers/runners/etc for self defense, and carrying a full size rifle or heavy SMG interfered their MOSThe US Army in 1944-1945.
U.S. Army Rifle Company (1944-45)
The organization and equipment of the U.S. Army Rifle Company on D-Day and later.
The U.S. Army Rifle Company (1944-45) with 6 Officers and 187 Other Ranks for a total of 193 armed only 23 men with the M1 carbine, 11 being officers or NCO, 12 being the buglar, the messengers and the amno bearers.
And one of the first thing, every officers and NCO learned in time of war is to carry the same gun, so a M1 rifle, that your soldiers to avoid being killed by a sniper because you have a handgun or a different gun than the others. I saw it wrote in many books about infantry combar or war memoirs.