All excellent points 65BR. I agree with them all.
Todate, I have worked up some dandy loads for the 6.5x55 (T3 8 twist) using 100 BT's, 120 TSX, 129 Hornadys and 140 Hornadys. I'm not as diverse with the 6.5x284 (Serengeti stocked MRC:twist unknown) yet with only 120 BT's and 130 TSX's that I would feel good enough about to hunt with.
I have seen your velocity estimate come across my chrono with the 129 Hornady, so you are spot on there. I think I had some room for more fps but my group said quit, so I did.
By this time next year I expect to have wrung out several more bullets with my 6.5's, including most you mention, and ready to do some serious shooting.
I'm new to the 6.5's, except for a couple military Swede's I've enjoyed, but always wanted a sporting rifle in a 6.5. Now I have two and I'm having a ball trying out new loads.
I fully understand and agree that "premium" bullets are a bit of a waste on a 6.5 and started with the Hornday 129 and 140, thinking those would always be good enough. Certainly they are more than good enough, but the 6.5 bug bit, and now I have a compulsion to make every 6.5 bullet on the shelf shoot at least dime size groups......well not fully true, but close.
Anyway, the Accubonds were relatively cheap and I like cheap bullets. I have 350 to play so I figure I better get started. With good success I'll be calling for 350 more.