because they operate at higher pressures to begin with, the 9mm and the .40 S&W lose less velocity than calibers like the .45 ACP. in my tests using a Pact II chronograph i have found that compared to the .357 Mag and the .45 ACP the .40 S&W and the 9mm generate velocities from 2.5 to 3 inch barrels losing only about 25 to 35 fps per inch from what a standard 4 to 5 inch barrel will do. this compares to the .45 and the .357 that generally loses from 50 to 75 fps per inch. this may not seem like much difference but when you are dealing with handguns every fps counts. i feel that the .40 S&W is the best choice for handguns with barrels 3 inches or under, the .45 for handguns four inches and over. the .357 Mag loses heavy in short barrels but still remains the cartridge of choice in snub nose revolvers.JMHO
------------------
Democracy is two wolves and a lamb voting on what is for lunch.
Liberty is a well armed lamb contesting the outcome of the vote.
Let he that hath no sword sell his garment and buy one. Luke 22-36
They all hold swords, being expert in war: every man hath his sword upon his thigh because of fear in the night. Song of Solomon 3-8
The man that can keep his head and aims carefully when the situation has gone bad and lead is flying usually wins the fight.
