That's been my observation as well. Even with 180gr sub-sonic loads the 40S&W feels like it generates more recoil impulse(muzzle flip mostly) then a 230gr 45acp load. This is one of the major reasons why I find I have no use for the 40S&W. Give me a 45acp or a 9x19mm any day of the week.Personally I think the perceived recoil impulse is milder than the .40's.