Tim beat me to posting the link to the disscussion we had whilst you was gone.
Because of that thread and further research I chose the one Tim has. The Chrony F-1 Master, a basic model with one funtion. Telling me the speed of one bullet, other models that cost more are basically the same only they do the math for you, I can do math. Finding the Standard Deviation is a bit complicated, but I found one of several on-line progams that do it (free).
The master models beat all the bad reviews, the remote display sit's on the table next to me and connects with a common telephone cable. I just jot down the info on a sheet and do the math at home. I'm not worried about haveing extra memory to hold the info, I got the data for the 10 rounds and that's all I need, 20 if I want. If you can bid a job, find distance of a 4-12 pitch or square a building you've all ready used math beyond what's needed for data.
All chronographs have issues with light brightness, snow and other conditions. I guess it's just a matter of experimenting/finding the proper way to provide what the photo cells need for light. They basically need a surface to reflect off of, a constant whiteish surface so they can "see" the shadow cast as the bullet passes. Direct bright sun shinnig on the cell can cause problem as it's too "light" for the shadow to be seen. Mount the chrono on a photographer tripod, tip it or even have it sideways so the sun isn't on it and the problem is solved. Bad reviews about any chrono because of sun shine just means the guy wasn't smart enough to figger it out.
I should have delivered in a few days a laser bore sighter, slide it down the bore, bag my gun so it on target at 100 and the laser will point bullet path to the 10 yard distance I need for the chrony,,I don't wanna shoot it just yet
