Good stuff, I always felt decades ago that the 6.5s may well kill better than most would imagine b/c fast ROT keeps the bullet nose fwd which ensures better straight line penetration thru vitals/POA. As a side benefit, debated often, faster ROT may add to the damage a bullet does in tissue. Something I seen illustrated in a test written up in a Handloaders digest from the 60s/70s. A 7.7" Mil-Surp Swede vs a 6.5 RM 600, using 129s and 125s shot into newspaper. The quicker twisted Swede had MORE bullet upset and a wider wound channel, albeit slower mv than the 6.5 RM. Read other similar reports over the years, perhaps some trught so it seems. None the less, I ALWAYS choose the 8 twist in 6 and 6.5s, and always prefer leaning on the faster side in any rifle, when given a choice. I don't shoot BR, where a smidgen of group size might go to the twist that is "Just enough" as that is meaningless in the field when bullets hit game IMHO. To me, MORE is better when it comes to twist rates, shy of jacket ripping RPMS. True I suspect a faster twist fouls a little more and causes more friction which can slow potential MV to a minor degree, neither are enough to worry me.