The nose shank on the Remington is stepped down from the rear portion. There is actually a ledge. While I never measured the bullets I pulled, it has to be smaller than .450 inches. I am going to guess that it is .448 inches. That is why it appears that the crimp does not contact the bullet. It it did, it would not head-space properly.
Also, if you notice the close up on the crimps, the Remington seems to be turned in more than the Hornady. Regarding the Hornady -- this was noticed by HOOT long ago -- is there appears to be a secondary ring on the mouth of the case. It is barely perceptible and you need a magnifying glass to see it. Looks like the case mouth contacted a sharp edge (all 450B Hornady ammo I have has this) during the crimping which turns a portion of the case mouth into the bullet while leaving plenty of surface to head space on. Who knows -- maybe this is a way to compensate for varying case lengths. I can not see it after the case has been fired. HUMMM! Part of Hornady's secret loading procedures to turn out top notch ammo?