Weight sorting .22 LR ammo for Benchrest 50 extreme precision

Sharing the results of weight sorting .22 LR ammo for Benchrest 50 (BR50) - sorting two 100 samples from the same production batches: one from Lapua CenterX and another from Akah X-Trainer.  Both are Made in Germany by Lapua - Center-X is a top of the line ammo costing approximatly twice as much as the low end Akah X-Trainer.

Test results for the Center X
 - the all 100 units batch is within a tight 0,2 grains precision interval  (!)

Test results for the Akah X-Trainer show a high spread in weight
Approx. 66% can be fitted in the 0,1 grains interval of 51,5 to 51,4

A "matrix sorter" helps to keep track of groups within different weights

A 0,1 grains precision digital scale

Next steps, since the 0,2 grains precision interval as "factory default" from Lapua Center-X is considered to be "match grade", and no further sorting should be required there, will be focused on measuring rim thickness. For that I'll be using a thickness gauge by Hornady , http://www.hornady.com/store/Rimfire-Thickness-Gauges . I'll report about that measuring process and data on a forthcoming post.

The Hornady thickness gauge applied to a calliper
(diagram from Hornady product manual)