Is this for a hunting or target set-up. If for hunting, I'd recommend bumping up to a 100gr tip, and trying something more like and FMJ 460, still gets you around 260fps but you also have 58ft/# of KE, whereas it also ups your FOC from about 6% to 8.8% which will help with BH flight. And with that set-up, I wouldn't recommend a Mechanical set-up, unless it's a small diameter one. You can stay with the 75gr head, and a 500 series and be spined well, but your FOC will be low which will be more likely to result in "flyers."