Some time back I sought help choosing a ballistic data gathering tool I'd wished for for decades. A shooter since the late 60's, I'd never felt I could afford a chronograph. Here I posted a request for help choosing one within my budget, and I chose a Caldwell set containing the tripod and LED illuminated screens. Only yesterday did I get to use it the first time, and that was with my wonderful nephew. Together, we learned the chrono's setup and use. Pleased with the results, despite some "err2" and "err3" readouts (likely user error in lining things up), we found the optimum number of pumps for velocities on his heavily modded Crosman 1322 pistol shooting RWS Superdome .22's, and my Benjamin 392PA carbine.
This tool is great, and will likely get many hours of use. The data was nice to have. I honestly had no idea my 392PA with 10 pumps and 18 grain AA pellets was cranking out right at 15 foot-pounds of energy at 15 or so feet from the muzzle. Mercy! Sadly we couldn't easily do simultaneous accuracy testing while gathering velocity date though. Until we have a bit more experience it was good enough to line the guns, chrono screens and the small bullet trap up at distance while not risking misses punching holes in my wife's and my yard barn at the back corner of our suburban yard. Or worse the neighbor's yard barn...
Thanks again to all here for the generous help.