Klik,
You may be right about the ogive shape.
I started using more X's with the advent of the blue-coated XLC, partly because the coating did reduce the fouling issue, though it didn't always solve the accuracy problems, by any means. But by the late 90's Randy had come a long way in solving the copper-supply variations, and the bullets themselves were also far more consistent. My rifles started shooting far more X's accurately, and I never experienced any problems with expansion even on pronghorns at 400 yards--though unless the bullet were coated the fouling problem remained.
The TSX's solved the fouling problem, but I did see a few fail to open, but only in calibers from .24 to .30, apparently because the hollow-point was so small it could be closed by recoil-slamming against the front of the magazine. Have never seen any .224 TSX's or over-.30 TSX's fail to expand.
Have been using TTSX's, E-Tips and GMX's since 2007 with zero expansion problems. The only time any has lost any petals was when they hit heavy bone.
