Thanks vzontini, that is a good check. That same check can be made when the slide is locked back, the striker and block will be accessible behind the beaver tail. it's an easy check to make sure it's safe. Could indicate if a good cleaning is in order or if there is a problem developing. What I was actually looking for was factory dimensions that might show the distance in thousandths of inch that the block should engage the striker. Probably that info would only be available to gun smiths though.