However, I haven't found any way to deaden the recoil, other than wearing gloves. I was wondering if these excellent looking grips were made of rubber or polymer or what not and if they help with the recoil of this otherwise excellent weapon?
The terrible, box stock, DA pull can be dealt with quickly and easily. There are several threads that discuss that fix. Further, many of us avoid the DA pull altogether, doing most of our shooting SA by thumb-cocking the hammer first.
Unfortunately the recoil doesn't want to go away. The difficulty really isn't so much a massive recoil -- it's not all that heavy. Rather the problem is that the recoil seems to get channelled down through the trigger guard directly to the fingers. Gloves do indeed offer some measure of help. The fancy grips add a lot to the appearance of the firearm, but do not do much in terms of eliminating recoil (the grips are a kind of hard plastic, rather than a soft rubber).
Also I have learned not to hold the pistol quite so tightly with the off-hand. We are often taught to use a two hand hold, whether Weaver or Isosceles, and to take a death grip on the pistol. Unfortunately, that tends to exacerbate the felt recoil with the P-64. Try to relax your off-hand a bit, and hold a bit away from the trigger guard. You may find that helps tame the sting.
Over time I have become quite used to the feel of my P-64. I even shoot 115 grain Silver Bear from time to time without much discomfort . However, I don't recommend using heavy bullets on a regular basis -- there's no point in beating up the gun (or yourself...) more than necessary. You may find that felt recoil is reduced substantially by using bullets of 95 grains or less.