I can offer (2) comparisons from different barrel lengths from (2) different guns. With the same load of 28.0 gr. of AA1680 and a Hornady 180 SSP, a 24" MGM barrel on an Encore frame produced 2205 fps and a 22" Ruger No. 1 produced 2165 fps. With two different guns other things like throat length, bore condition and size all come into play. Without staying with the same gun, starting with a long barrel and cutting it inch by inch and recrowning between cuts, it's difficult to say for sure. Faster burning powders like H110 will reach the point of diminishing returns on barrel length quicker than slower burning powders like 1680 and RE7. 1680 is on the slow side so longer barrels may show a bit more velocity. I do agree with JY that shorter barrels are more accurate than longer barrels. Since these guns are typically used for hunting, the benefit of a longer barrel to gain velocity for a flatter shooting and harder hitting round may offer some benefit but this is for the individual to decide. Strictly my own opinion, I think with the .357 Maximum, a hunting rifle is at it's best between 20-24" and a heavy barrel is even better.
Good Shooting,
Steve
