Tikkamike,
Give them a call or an e-mail. I e-mailed a comment to them a few months ago and was very surprised to see it promptly responded to the next morning.
I don't have the D59s or D64s. I do have some D65s and they measure 1.810". I also have some 225 grain D62s, which measure 1.635.
I shot the 225s some this past season hunting. I am running them at about 3500 out of my 338Khan. They shoot very well and with the BC and higher velocity I am getting out to 1000 with a full 5 moa less dial-up compared to the 300 grain bergers. 50" less drop at 1000 is enough to get my attention.
I shot two critters with them, a whitetail doe at around 300 yards and a whitetail buck at about 450. Both were good hits tight behind the shoulder. The doe ran about 150 yards, the buck made it about 50. Wound channels were impressive and overall I cannot complain. However, I have been used to shooting 250 or 300 SMKs or 300 Bergers for the last several years. Both of those shots would have rolled the deer up right on the spot rather than the short run they both made. I think is fairly typical of the solid type bullets as I have had similar experience with Barnes in the past. Don't get me wrong, I'm not knocking the terminal performance of the CE bullets, just don't expect them to deliver the same energy to the critters as the more fragile bullets like the SMKs or Berger.