Jason, in my fit of amazement all I can say is : Shazam (Gomer Pyle's word for "holy sh--")

You must be using paper targets since the bullet splash at chickens would not allow you to do what you describe and I doubt you go down range to examine each chicken as you hit it.

Specifically, 1 click at 40 meters is about .1093 inch or less than 1/8 inch, 2 clicks less than 1/4 inch. What does you rifle consistently group off the bench at 40 meters? Certainly not an 1/8 of an inch does it? I suspect it would be closer to 1/4 inch so a shot that is .25 inch from you called hold could just as easily be within the accuracy standard of you gun. What am I still missing??

I must say I am not as "uneasy" about this whole subject now that we talk about it but I am "blazingly mystified."

Yes, I shoot at paper for both bench and offhand sight-in, or occasionally at swingers if they aren't all marked up already. At 40 meters off the front and rear rests, my groups are usually about two bullet hole widths at most assuming that I have some sort of usable wind flag to watch and that wind isn't a factor. Being 1/4" high (more than a bullet hole width) is pretty easy to notice if it happens for a couple shots in a row off the bench. It takes more than just a couple shots offhand before I trust moving just a click or two. You're right in that it would be much harder to sight in precisely without a good spotter if there were only freestanding targets to knock down.