Let me start by saying Dennis is a excellent guy,but I've had 4 sets to break,he replaced them no charge to me everytime.The latest design I have now but haven't had a chance to shoot with them yet.Torpeau, a fellow member has, and they also broke on his.I cannot recommend them for the P64 as I can twist mine back and forth about 2mm,therefore I know there going to break when shot.Until this design is completely substantiated, I cannot recommend anything but the factory grips,IMHO! :-X
protectror,
I too am sorry to hear about your grip problems, and it is hard for me to understand why this keeps happening to your grips. I remember when Bobby J. sent his original P-64 grips to Dennis for him to use in his CNC set up to design the wood P-64 grips. I got a set of checkered red wattle grips not very long after Bobby J received the first set of Dennis's grips. My first set broke at the top where the two pieces came together at the back. I sent Dennis a pic of the grips and less than two weeks I had another set, however, I requested that the new set not be glued but rather come with the two sides separate just as the original grips on the P-64. I have used the second set on both of my P-64's, a 1969 and 1976, with out any problems. BTW, I glued my set that broke with Gorilla Glue and they also have held up just fine. To my knowledge this is the first time I have heard of anything happening like this, I'm at a loss for what to say.
I can't help but think that something is different about your pistol, I realize that is a stretch, but I can't imagine what else it could be, unless you possible have tightened the grip screw to tight and even then I not sure it would break. I guess its possible that there is a flaw in Dennis's CNC equiptment, but after replacing that many grips for you I would have thought he would have checked everything out. Wish I could be of more help.
papabear