The lighter the gun, the easier it is to feel the difference. I certainly can in my P938.I use to think it made a difference and I am sure it dose but can you really feel it or tell for me no when i load them separate I thought I could then one day just for fun i loaded a few mags with random weights and could not tell which I was shooting at all. I think for most people its just all in your head If you think 124 feels lighter it will.