Before you jump into purchasing a chronograph you need to consider a few things.
The first thing is are you reloading? If you are then a chronograph can give you some useful information but few people know how to analyze it. They also get caught up in the numbers and forget about the target.
Second, If you are shooting rimfire then you'll get data but for what use? You can't do anything about the data and the target will tell you everything you need to know.
I would highly recommend you read the series on statistics on the Precision Rifle Blog. Here is the link to the first article in the series.
I actually believe the average shooter might get more value from this Statistics for Shooters serie...
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