I tried closing the bolt on my Howa 223 with Hornady 55 grain SP factory ammo. Bolt moves maybe a third of the way and becomes tight very quickly and immovable. Tried about 5 rounds and all pretty much the same. Measured case head to shoulder and found compared to other factory ammo, the Hornady is on average, roughly .007" longr from head to shoulder datum line. I find it hard to believe that factory ammo will not chamber in a factory gun, but... I do see a fine tiny scratches around the edge of the case body and shoulder. PMC Bronze ammo chambers fine. I have cleaned the gun, but maybe some piece of debris is in the chamber. Other ideas?
Phil
UPDATE 12/8/2013
I forgot that I had a Wilson Case Gauge, that would quickly tell me whether the Hornady 223 factory ammo I had was within SAAMI specs. So, pulled out the gauge and tested the Hornady ammo that would not chamber. They all fail. All sit above the top level of the gauge. A small steel ruler set across the top level of the gauge rocks on the case head and will not sit across both side of the Wilson gauge. Clearly, the Hornady ammo is out of spec. Other factory ammo I have easily fits within the Wilson gauge, and it chambers just fine.
Phil
UPDATE 12/8/2013
I forgot that I had a Wilson Case Gauge, that would quickly tell me whether the Hornady 223 factory ammo I had was within SAAMI specs. So, pulled out the gauge and tested the Hornady ammo that would not chamber. They all fail. All sit above the top level of the gauge. A small steel ruler set across the top level of the gauge rocks on the case head and will not sit across both side of the Wilson gauge. Clearly, the Hornady ammo is out of spec. Other factory ammo I have easily fits within the Wilson gauge, and it chambers just fine.