Not true, see below.
Do you actually zero at 200? I.E.- put up a two inch target for example, and at a 200 yard range make all of your rounds impact inside of that 2” target while aiming directly at it? Or, do you do what desertcj and almost everyone does, and zero a couple inches high at 100?
So let’s go through a thought process.
If you are fire a gun at an animal (or target) the goal is to hit it, correct? Well every shot has a hit rate, and it is never 100%. 100% certainty does not exist. With that, then we have to try and get as close to 100% as we can. To do that, you eliminate as many variables as possible The start of minimizing variables and in effect maximizing our hit rates on any target, at any range, is a solid zero.
Philosophically a zero is when your entire cone of fire (group) is landing point of impact directly on point of aim. You can not have a 200 yard zero, unless you are shooting 200 yards, and your mean point of impact (center of all rounds fired) is directly over your point of aim. If you zero “1.5” high at 100” you do not have a 200 yard zero. You at best have a 1.5” high at 100 yards zero.
To demonstrate this point- I see a hundred or so shooters a year that use something other than a 100 yard zero. I have never seen a single one that was actually zeroed at what they say they are. If they say they are zeroed at 250, they do not have their group centered over the target at 250 when we shoot. If they say “2 inches high at 100 yards”, we place a 1” circle centered two inches high over their aiming spot. Not one has ever put their rounds all in the dot- they are always off.
Let’s say you actually do get a perfect 200 yard zero at 200 yards. Do you account for wind drift? In my present location, with wind that is light for normal, there is a .3-.4 mil drift at 200 yards. If we had 20 guys from Rokslide on a range zeroing at 200, I would be utterly shocked if more than one or two accounted for the windage error. I would expect that everyone of them if they even thought about it would say “wind is light, no big deal”.
Do you account for errors in range? I’s the berm truly 200 yards? Or it 220 yards? What do you do if it is not exactly 200 yards?
So reason #1 for a 100 yards POA/POI baseline zero is: if we start with an error built in to our “zero” everything else will be built off of that error, and hit rates at all ranges will go down. Zero at 200 yards in a 5-6 MPH wind, or worse “zero” at 100 yards “x” high, have the target actually be at 215-220 yards instead of 200... and you can go from a 90% hit rate on a animal at 400 yards, to 50% hit rate REALLY quick and it takes a lot less small stuff than most think for it to happen.
Now what happens when you need to check zero? Could be just a pre hunt check, or because you dropped the gun and need to make sure it’s good? Following the principle of POA/POI from above, how often will you be able to find a 200+ yard range in no wind conditions to do so? If you can’t, do you just fudge it and hope?
The benefits of a 100 yard baseline zero (that means point of impact of all rounds fired is exactly centered over point of aim, and turrets slipped to “0”).
A 100 yard zero is within .1 of an inch, from 55’ish to 120’ish yards. What that means is following POA/POI principle is that I can make the bullets fall directly behind the crosshair at any range between 55 and 120 yards and have a 100 yard zero.
100 yards minimizes environmental effects such as wind, temp, barometric pressure, etc.
A 100 yard zero is the only “zero” that you are always dialing/holding “up” for. The bullet doesn’t cross your line of sight.
With scopes that work correctly (in this case a SS 3-9x), if I want to walk around hunting with the gun set to 250 yards, I simply dial “up .7 mils”. Now the crosshairs are hitting at 250 yards... or any other range I want.
Done logically and to maximize hit rates, there are no reasons for rifles with scope that dial to be baseline zeroed at anything other than 100 yards.