Thread: Chronograph thoughts

I have a Pro Chrono plus and a F1 Chrono. I find they can be sensitive to certain light conditions and overcast days are good for the best results. On sunny days the sun shades are a must. I have lined both mine up end on end so I could fire a shot and get a reading on both machines with the same bullet, results were about 20-30 fps difference.
What you can now do is do the shoot test. You can do drop charts for both the speeds you have got and then shoot at a target at say 400 yards and measure the inches drop and compare it with what the drop chart tells you it should be. If the actual drop is the same as say the 2600 fps drop chart inches drop you will be safe to say that speed was correct.