There are a few reasons we tend to steer people in the direction of 124gr 9mm over 115gr. The main advantage of 124gr 9mm over 115gr 9mm is that it has a higher muzzle velocity and energy. This means that it has more stopping power and is better suited for self-defense and target shooting. Additionally, 124gr 9mm rounds tend to be more accurate than 115gr rounds due to their heavier weight. There are some who say 115gr is “snappy” compared to 124gr… run your own tests and see which cycles the best through your weapons and which you feel more confident shooting.