Last week I tried to chrono my factory rounds. See below from earlier post. I obviously did not get the factory velocity that I was looking for. Any help that you can provide will be appreciated.
I was at the range yesterday shooting factory Remington Safari Grade 160 gr A-Frame rounds out of my Sako AV rifle. I've shot these rounds out of this rifle for a dozen years with very god results. I had decided that I wanted to try to duplicate the round in reloads so I set up the chronograph to determine the speed. This is the first time that I've checked the velocity of these rounds in my rifle. The muzzle velocity on the box states 2,900 fps.
I fired five rounds with very inconsistent speeds of 2868, 2994, 2953, 2976 and 2922. The grouping was not as good as normal. I let the barrel cool down before shooting the next round.
When I fired the sixth round I felt blow back on my face and wondered what the hell happened. The chrono logged the shot at 3,190 fps (290 fps over listed) and the bolt was locked up. With the help of a mallet and rod I was able to free the bolt and found the extractor was broken. Now I'm scared to shoot any more of these rounds.
