14.5" 1/7 twist M855 zero

[Plumber237]

Here is my kit I am running, basically I am just wondering what my optimal zero distance should be:
14.5" BCM Mid-length
1/7 Twist Barrel
Aimpoint M68 (Comp M2)
Federal M855
I am currently zeroing at 25 meters.
It is a home defense/shit hit the fan rifle, no competition shooting.
I live in the city, so most likely no longer distance usage.
Thanks, Plumber

[Frens]

I am currently zeroing at 25 meters.
It is a home defense/shit hit the fan rifle, no competition shooting.
I live in the city, so most likely no longer distance usage.


seems like you're GTG.

I zeroed my carbine at 50m because my range doesnt have a 25m line but I've found this zero to work great at 25m (during IPSC match), 100m and even 200m.
keep in mind I have a 6MOA dot :D reticle on my compact ACOG

[Failure2Stop]

A 100 meter/yard zero will give the user a more gentle upward trajectory slope, making for less drastic hold-over changes at close range.
The 25 yard zero is one of the most inefficient zeros for anything other than shooting at 20 to 30 yards only.

[markm]

Yeah. Definitely try to get to a hundred yard range. A 25 meter zero can really mask a lot of error.

[Failure2Stop]

Yeah. Definitely try to get to a hundred yard range. A 25 meter zero can really mask a lot of error.

Another very good point.

50, 100, and 200 yard/meter zeroes tend to work out the best.

[JSantoro]

Here's some supporting info RE: the hows, whys, and wherefores of some of the more common AR zeros used: https://www.m4carbine.net/showthread.php?t=65679

SCIENCE!

http://img521.imageshack.us/img521/2231/sciencemx.jpg

[aveisone]

I like to use the 50/150 zero. This leaves me ~3" low at 25 yards. Just train to remember height over bore at close ranges and this will be good for getting hits from 2-200 yards.

[Eurodriver]

I zero all my weapons (minus anything with a BDC) at 200 yards.

At point blank ranges, just train to put the dot on the forehead. Makes for a perfect t-box shot.

I would rather know my POA/POI at a distance thats farther than what I am likely to encounter than closer.

[Failure2Stop]

I like to use the 50/150 zero. This leaves me ~3" low at 25 yards. Just train to remember height over bore at close ranges and this will be good for getting hits from 2-200 yards.

What bullet and muzzle velocity are you using for a 50/150?
Usually a 200 yard zero will have it's initial point of trajectory/line of sight crossover at around 50. Of course, a really heavy, slow projectile will change that.

[a0cake]

+1 on everything Mark, F2S, and Santoro have said.

I'll add that if you absolutely cannot find a ranger that extends beyond 25M (I know it's hard in the city), you can zero 1.5'' low at 25M. This will give you a rough zero at 100. As Mark mentioned, zeroing at short range can mask a lot of error, so take care to be as precise as possible to mitigate the effect. Still, nothing replaces the act of actually shooting at the desired zero distance. If I only had 25M available, this is what I would do though.