Thread: What's going on here??

Greetings again,
Looking at those velocities again the 136 fps loss of velocity is HUGE. It is equivalent to dropping the charge by two and a half grains. It is really important to find out what the problem, and there is a problem, is and correct it if the rifle is to be used at longer range. So please more information is needed starting with the powder charge and how it was measured and with what. What was different between the start and end. What was the chronograph and how was it set up. In no particular order I would suspect:
Chronograph error due to bright sunlight or varying set up.
Inaccurate powder measurement.
Loose suppressor.
Cartridges left in sun.
And many, many more.
Regards Grandpamac.