The S&W 610 revolver uses "moon clips" so head space chamber length is not an issue. It will chamber the 10MM Auto without them but the extractor will not eject the spent cases. You have to poke them out one by one.. COL is limited by the length of the cylinder instead of the chamber and magazine. Velocity?? Barrel gap/forcing cone vice a closed chamber? I would guess the 6.5" barrel would compensate. I don't know of any semi auto that can shoot both 10MM and 40 S&W without a barrel change of some sort. The N frame is meant for 44 Magnum so it will take the punishment. 610's are getting to stupid prices now, but one can rebore the cylinder out longer to shot 10MM Magnum, 10mm Auto, 40 S&W.