Nine grains, but the Hogdgon data shows a difference of 2,000 PSI energy.I personally would be unable to tell the difference between the two based on recoil. I'd have to look at the weight printed on the box. It's a pretty trivial weight difference. We're talking about only 9 grains. That's not even 8%. And the other factor in recoil is speed: the 124s are going a tad slower which -- all else being equal -- would reduce recoil. It's just too close for me to notice.