How far do you set up the chronograph from the table?
I think my friend had it too close....had a lot of "error" readings. (He was shooting 308)
About ten feet. I had it too close earlier and was causing errors for the higher loads out of my varmint .223, probably from excessive blast. My AK and 300BLK have muzzle breaks so no problems. I haven't had any problems with my Mosin Nagant (.312") except when the wind knocked the chrono over. I have since perfected the sandbag weight on the tripod.
With the tripod, the limiting factor is the height and line of sight to the target. The far left table is flat in front and the slope increases to the right, especially past the RO office. However with my large stature, I have difficulty using the smaller tables that are more prevalent to the left.
Overall, the main problem is set up which takes 15 to 20 minutes. I haven't tried it yet during the 5-minute break. If I arrive on the weekends after 8 am, I'll have to use the first break to set up my targets, then use the next break for setting up the chrono in front of the table. Doable but a pain. Plus if the tables are full, it's harder to choose the best table. As with everything related to shooting, I'll likely upgrade next year.