No particular reason other than the 124 grain bullet is what the 9MM luger was originally designed to shoot plus it's the weight of the 9MM Nato. The 147 grain bullet being designed originally for sub-sonic loads is a heavy for caliber weight bullet and I just prefer a middle weight for caliber bullet in most all my guns. I like the 124 grain bullets being a little more deeply seated in the case than 115 or lighter bullets. Plus in my 2 pistols and one carbine rifle the 124 grain bullets have shot well and my sights seem to match the point of aim of the 124 grain bullets impact point. Nothing wrong with the 115's or 147's in 9MM but I've just settled on the 124 grain weight bullet.
Last edited by rg1; October 2, 2012 at 12:19 PM.