Following Stephen Camp's lead, I have the Remington version of the FBI load in my 637 Airweight. From Stephen's soggy-newspaper tests, it probably will expand when fired from a snubby, whereas the harder Winchester and Federal versions probably will not (from longer barrels, they probably will). The Remington bullets are really soft. If you drop them, they become range ammo the instant they touch the ground. They are also quite stout from an Airweight, but what +p ammo isn't?

Cordially, Jack