I was wondering if some of you guys with knowledge of reloading could help me out with this question. looking at switching to some monolithic bullets for my .308 for Elk sized game and the nosler e-tip in particular is high on the list. In case my rifle doesn't shoot them well I was looking at the Hornady GMX option since I know my gun likes the 150 and 165g SST rounds. my question is, why does the GMX have a slower muzzle velocity than the same weight bullet in the SST? example .308 150g SST Superformance is 3000fps 150g GMX is 2940fps only 60 fps slower. but when you step up to the 165 grain GMX which I'd like to use for Elk its 90fps slower 2840 vs 2750. from what I can see they have the same ballistic coefficient and same weight. does it have to do with bullet length taking up power space? I've heard the GMX might not expand at lower .308 velocities very well. Does anyone have experience with this round on elk sized game?