I am not a carbine fan though I own a couple of CMP carbines.
Every year my gun club has a Garand, followed by a carbine match using the 100 yard reduced targets.
We have High Master shooters who will bring out match grade Garands and shoot somewhere between 450 and 470 out of 500, or we have HM shooters who bring out rack grade Garands and they will shoot up to the 440’s.
Then we shoot the carbine match. These same shooters are lucky to break 400. For decades the high score was in the 420's. A good carbine will just hold the 5.75" black at 100 yards.. A carbine is hard to shoot well as it is light and twitchy, the triggers are awful and no one has figured how to get a match trigger pull.
Shooters have brought out commercial carbines and they shoot better than GI. I am of the opinion that WWII carbine barrels are of poor quality, better quality barrels will tighten up groups.
Shooters have tried all sorts of bedding techniques but no one will call their carbine a match rifle.
This carbine was shot by the match winner and is interesting as you can see some of his modifications. This a National Ordnance carbine and National Ordnance had old rusted out carbine barrels and new M1903A3 barrels. The gas system on a carbine barrel is integral to the assembly so to use the rusted out barrels they drilled and reamed the barrel out of the carbine barrel end , turned down an A3 barrel, then soldered to the A3 barrel inside the shank. The match winner claims this shoots better than a standard carbine barrel.
Carbines were created as a pistol substitute and the hit probability with a carbine is much better than a M1911 pistol. But the carbine remains a pistol substitute no matter how much people want to expand its capabilities.