If you are looking to 'verify' that it is throwing accurate charge weights, then just don't buy it in the first place and get a better scale/system to start with. The chargemaster is good for loading plinker and hunting rounds at best. I'll spare you the wonder about verifying the weights - it's going to be +/- .2 grains on average.
Buy once, cry once, trust me. I have spent probably a grand on beam scales, other digital scales, and the chargemaster over the years. Up until a few months ago the accuracy of my powder charges have been a best guess at best. Finally broke down and bought an autotrickler setup coupled to and A&D fx120i scale. I now have accuracy down to the kernel, and it throws charges 2-3 times faster than the chargemaster.
This made me truly LOL.
Fuck man I should tell my Labradar those ES 3-5 I am getting on my 6BR are false. And I had a hell of time yesterday "plinking" from 560-1200 yards.
Chargemaster is fine, if your shooting benchrest with your name and a sponsor on your shirt then go buy something more. I had an fx120 that I got from a physician with more money than sense and while it was nice it was not noticeably more accurate than my chargemaster. It is fast I give you that but using the insert and the mods my chargemasters are faster than me. I sold it got a dillon press (that I never use but need to one of these days...) and another chargemaster to hold H4350 so I rarely need to change powder.