I have developed an Apple Watch app called WatchForce. I wanted to record the motion and forces an Apple Watch can detect via the accelerometer and gyroscopes.
I have used this app on thrill rides and roller coasters, AND I have used it while shooting pistols.
Here is the G-Forces recorded while shooting my CZ 85B.
Now I know that an Apple Watch and iPhone are not inexpensive, but hey, if you have them already you can use the app to discover some interesting information.
Here I select the data and I can see very precise values including their times.
Since this is done via the watch and not using sound, there is no interference from others at the range.
What other things might you want to measure?
Here I measure the recoil recovery time by selecting the point where the shot is clearly underway, the highest point, and the first point where the motion has settled down.
I find it interesting. Maybe if I could get a few hundred or even thousand data sets from users I could Machine Learn a very sophisticated shot analyzer. This is a starting place at least!