Re: 308 win lead free Factory hunting round
If all you have access to are the factory Vor-TX loadings, either the 150 or 168 will provide hits within a deer's vital zone using your 168 FGMM sight-in upto about 350 yards.
I'd have picked the 150 TTSX for smaller game like whitetails as it expands quicker, or 130 TTSX if you handload.
Beyond 500 yards or so (well beyond the expansion range of the 150 or 168 TTSX in a .308) the 150 TTSX is ballistically closer to the 175 FGMM.
At the distances you're shooting at, just about anything would give you hits within an inch of your 168 FGMM sight-in; I'd just pick Federal Vital Shok 150 TSX, or either TTSX Vor-TX loading, whichever was on sale.