While we are here and velocity plays an important part in stopping power, I was amazed to see the disparaging differences even within a single caliber. My research did produce a few winners .357 mag .41 magnum and 44 magnum when compared between a 4 inch barrel and a 16 or 18 inch barrel carbine. Otherwise I can see much benefit except concealment over a 4 to 5 inch pistol compared to carbine length rifles in any other caliber if there is any doubt go to Ballistics By the Inch here is the web site Ballistics by the inch tables for 2 to 18 inch barrels
To my surprise the least contender for improvement was the 10MM velocity wise.
I do ask people to also go to gundata.org for bullet drop chats by caliber here is the link Gundata.org bullet drop charts by caliber
Comparing the bullet velocity and bullet drop gives you a reasonable assumption of the range and power on a flat trajectory. Although not a given but a good marksman could effectively use a carbine out to 3 MOA and for the magnums is out to 125 to 160 yards. Out of personal interest I looked up 9MM and it appears that @ 100 yards had a bullet drop of 12 inches and flat trajectory was only out to 35 yards give or take from there it went quickly south so anyone using a 9MM carbine would have to be very aware of range to maintain accuracy, even with a bullet drop optic you could count on mental calculation in a time of crisis might be a tad difficult IMHO.