Rourke linked to an excellent pictorial about ballistic trajectories from different zero's over at M4.com.
Let's look at the trajectory using a 25 meter zero.
If you look the bullet path is 8 inches high from roughly 125m to250m. This is a real problem. This is enough of a problem that folks will miss targets. In fact that is what happened.
My informal understanding of the development of the 50 meter zero is as follows. Dudes were missing Tango's in the 100-150 meter range which was pretty close to the max range guys found themselves fighting at in Iraq (yes there was that occasional long tail fight which was further but lets not get into the weeds). After some consideration, or quite frankly I'm not quite sure what, the SOF community began to transition to a 50 meter zero. This trickled to varying degrees into the conventional Infantry guys and the shooting community at large. That is how the 50 meter zero came about in my understanding. If anybody (John Mosby, K or Lizard Farmer come to mind) has a better understanding of that development through something other than reading on the interwebz I would be interested in hearing it.
So let us look at the 50 meter zero.
As you can see this zero is much flatter. From the muzzle out to 250 yards or so (varying slightly by barrel length, twist, etc) the bullet is at +/- 2 inches. This is what matters. Granted I might need to hold over a little bit at longer distances but inside 250m it's just muzzle on target, relax, squeeze trigger. Since the vast majority of military engagements happen well inside that envelope to me it is a very easy decision to make.
I use a 50m zero for my fighting rifle and recommend it to others. I do not think your choice of optic should affect the zero chosen. The 50m would be my choice for iron's, a red dot or a scope. It's pretty awesome on my Burris MTAC. Really the only reason I can see going with another zero would be a gun with a concept of use other than a fighting rifle. For a DM or varmit gun I might look at a 36 meter zero to keep it within 4" out to about 350 meters.
The way I personally execute a 50 meter zero is to just do a 25 meter zero then back out to 50 and adjust the point of impact down to be on at 50m. The reason I do this is that it's a lot easier to get onto paper at 25m saving ammo then back it out to 50m. I think it's faster and certainly saves ammo by starting closer to zero (due to distance). Suppose I could move the sights sufficiently then confirm but I've been lazy and redneck adjusted (fire a group, move the sights, repeat as needed till on target).
Anyway that is why my rifle is zeroed at 50 meters and I suggest you do the same. That is my thinking on that.
Let's look at the trajectory using a 25 meter zero.
If you look the bullet path is 8 inches high from roughly 125m to250m. This is a real problem. This is enough of a problem that folks will miss targets. In fact that is what happened.
My informal understanding of the development of the 50 meter zero is as follows. Dudes were missing Tango's in the 100-150 meter range which was pretty close to the max range guys found themselves fighting at in Iraq (yes there was that occasional long tail fight which was further but lets not get into the weeds). After some consideration, or quite frankly I'm not quite sure what, the SOF community began to transition to a 50 meter zero. This trickled to varying degrees into the conventional Infantry guys and the shooting community at large. That is how the 50 meter zero came about in my understanding. If anybody (John Mosby, K or Lizard Farmer come to mind) has a better understanding of that development through something other than reading on the interwebz I would be interested in hearing it.
So let us look at the 50 meter zero.
As you can see this zero is much flatter. From the muzzle out to 250 yards or so (varying slightly by barrel length, twist, etc) the bullet is at +/- 2 inches. This is what matters. Granted I might need to hold over a little bit at longer distances but inside 250m it's just muzzle on target, relax, squeeze trigger. Since the vast majority of military engagements happen well inside that envelope to me it is a very easy decision to make.
I use a 50m zero for my fighting rifle and recommend it to others. I do not think your choice of optic should affect the zero chosen. The 50m would be my choice for iron's, a red dot or a scope. It's pretty awesome on my Burris MTAC. Really the only reason I can see going with another zero would be a gun with a concept of use other than a fighting rifle. For a DM or varmit gun I might look at a 36 meter zero to keep it within 4" out to about 350 meters.
The way I personally execute a 50 meter zero is to just do a 25 meter zero then back out to 50 and adjust the point of impact down to be on at 50m. The reason I do this is that it's a lot easier to get onto paper at 25m saving ammo then back it out to 50m. I think it's faster and certainly saves ammo by starting closer to zero (due to distance). Suppose I could move the sights sufficiently then confirm but I've been lazy and redneck adjusted (fire a group, move the sights, repeat as needed till on target).
Anyway that is why my rifle is zeroed at 50 meters and I suggest you do the same. That is my thinking on that.

