Jhunter
Accuracy and precision
https://www.garmin.com/en-US/p/771164#specs this is new and getting good reviews from the precision crowd. 150 ES is still going to hit a human size target within 600yds. I’m not sure you will be able to produce benchrest accuracy with the components mentioned in this thread. I’d factor in target size and distance before making an investment into a high performance chrono. Also scales have an error in accuracy. You could buy a few 1000 rounds of factory FMJ for the cost of lab scales and high dollar chrony.