WV, if those are the older glue on models (meaning, not recently delivered to you), yes they did have some heat treating issues with a few batches. I busted up a few also, sent them back with a letter explaining, and they sent me brand new ones. All of the new stock I've gotten have not had this issue. This was also only with the glue-ons...the screw in had no such problems...wish they made a 300 screw in, the face of the screw-in models is much larger than the glue-on.
Best small game/stumping head out there right now, in my opinion.