I've never tried it out of a carbine, but the Remington 158gr jhp expand in water jugs out of both a 2.5" and a 4" barrel without difficulty. I think it would do fine in a carbine for your purposes. It's manageable in the snubbie - although it's a steel K-Frame, not a j, so it's heavier in the hand than your 640. A poster on this site said his department used the load and it was effective out of any barrel they used.
Remington markets that load as part of its "HTP" line now, which is relatively affordable. It used to be "Express," but as far as I know it's the same load.
