3 identical factory rifles
So I have the opportunity to have 3 Howa Mini 223s here, all with 20' light barrels. I'd like to shoot them as a set and establish just how they shoot with various ammos. I'll use groups of at least 10 shots at 100M and using a variety of factory ammo and reloads. I'd like to explore a few things like barrel heating (fast groups versus slow ones), accuracy and one rifle will have a variety of tuning tweaks etc.
I'm interested in ideas on what sort of tests would interest people. I'm not a scientist so although I'd like to minimize variables, the results might not be that useful, just sayin!