My original thread can be read here, if you are interested: Hornady Critical Defense & Securty Six
Got the replacement ammo last week. They replaced both boxes, but no explanation with the new ammo. I stopped by after work Friday and talked to the tech who checked it out. He had checked the ammo in the pressure barrels and a couple guns they have on hand. The pressures were fine, but the cases appeared to be soft, as they stuck in the S&W revolver.
Saturday I shot six rounds through my Security Six, no hangups, no problems, and the rounds look like they should, no flattened primers and the firing pin strike was smooth, no extrusions.
Unfortunately, I have no idea of the lot # of the ammo that had the problem. I had moved the ammo into a plastic box and failed to note the lot #. It was purchased over a year and a half ago.