Scope testing- shooting vrs not

[foreign]

Why is it that people do scope bow tests via shooting. Why not just put the rifle in a vice, draw a grid ( 1 inch at 100yrds,1/2 at 50 ect) and go through tracking test like that? Would save ammo and take out the variable of your shooting and the gun.

Or am I missing something?
thanks

 

[Bravo 4]

Recoil can do funny things to scope internals. My latest debacle with Leupold involved a MK4 that tracked 99% true but would shift POI about every 3-5 rounds.