Just returned from the range after test firing my Howa 1500 (223 rem). Your solution for ending pierced primers works perfectly. My frustrations over months of attempting to solve this primer piercing have finally ended. I had tried everything from switching brass, primers, increasing throat, new firing pin spring, switching entire firing pin assembly, checking headspace, neck sizing brass, outside turning necks and nothing worked. At one point of giving up hope, someone finally directed me to your web site. From that point on, all I had to do was send my rifle's bolt to Gre'-Tan for your fix and now everything works perfectly. Worth every penny.
Clyde Kirby, El Paso, TX.