dphobby,

The petals shearing off of the sabots isn't always an indication of sabot failure- I know that the sabots supplied with PR's Dead Center bullets are designed to shear off. I've shot the .357 195 grainers and been very impressed with the accuracy and consistency (although less impressed with the price).

On the other hand, my favorite load right now with my .45 is 95 grains 777 fffG with a Hornady 200 grain SST, and I've never had any petals shear off. Maybe Hornady's sabots are made a little tougher??? I doubt that 5 grains of powder would make enough more velocity to start damaging the sabots.

You could either try backing off your powder charge by 5 or 10 grains, or try some SST's instead and see if you have better luck.

Also, if you're shooting 1.5 inch groups, I wouldn't complain too much. The best 3-shot group I've ever shot with the load mentioned above was 1.25". Average group size is probably more like 1.75". Hope you get it figured out!