Whats your Red Dot Zero? 25-50-100 yrds?

**nickdrak** · 07-23-09, 22:18

Here's another excellent article on zeroing your AR by Chief Jeff Chudwin: http://www.lawofficer.com/news-and-a..._gun_zero.html

Trajectory Chart: http://www.lawofficer.com/Images/cha...CD422FC9A423D8

**RogerinTPA** · 07-23-09, 22:31

Anyone have a 50 and 100 yard trajectory chart for 62 grain ammo?

**M4tographer** · 07-23-09, 22:40

100 for me, Aimpoint Comp M2/M68. I'm not trying to work past 200 with it. I've got other rifles for that.

**nickdrak** · 07-23-09, 22:47

These Ballistickers from Ned also come in handy: http://www.m-guns.com/tools.php

**RogerinTPA** · 08-18-09, 21:07

Any chance of the Mods making this thread a sticky???

**Ming_the_Merciless** · 08-19-09, 11:42

The graph above summarizes the BZOs at 25, 50, and 100 yards for Federal XM193 through a 16" barrel with EOTech users in mind. Included is an EOTech range estimation reticle diagrams shown in Mike Pannone's M16/M4 Handbook on page 82, which on a side note is a great reference material that can be carried in an admin pouch or range bag. Moreover, for simplicity sake the numbers associated with hold offs at each zero line was, and the data I used was shown in a diagram featured in Kyle E. Lamb's book, Green Eyes and Black Rifles. For other shooters, if I get some time, I could also do the same for 62 Grain, and 77 grain.

In case someone wanted to make a quick ballistic program to only account for bullet drop, here are the details for the curve fitting I used. The curves above used a 9th order polynominal which offered the lowest residuals.

x = Represents range in yards.
y = Hold off in inches.

XM193 - Zero @ 25 yards
y = p1*x^9 + p2*x^8 + p3*x^7 + p4*x^6 + p5*x^5 + p6*x^4 + p7*x^3 + p8*x^2 + p9*x + p10

Coefficients:
p1 = -3.5463e-021
p2 = 6.521e-018
p3 = -5.0783e-015
p4 = 2.1817e-012
p5 = -5.641e-010
p6 = 8.962e-008
p7 = -8.7244e-006
p8 = 0.00026437
p9 = 0.092573
p10 = -2.3732

Norm of residuals =
1.5163e-012

XM193 - Zero @ 50 Yards
y = p1*x^9 + p2*x^8 + p3*x^7 + p4*x^6 + p5*x^5 + p6*x^4 + p7*x^3 + p8*x^2 + p9*x + p10

Coefficients:
p1 = -4.7044e-021
p2 = 7.9802e-018
p3 = -5.6502e-015
p4 = 2.1704e-012
p5 = -4.9281e-010
p6 = 6.7563e-008
p7 = -5.6588e-006
p8 = 5.4638e-005
p9 = 0.05442
p10 = -2.4483

Norm of residuals =
1.6582e-012

XM193 - Zero @ 100 Yards
y = p1*x^9 + p2*x^8 + p3*x^7 + p4*x^6 + p5*x^5 + p6*x^4 + p7*x^3 + p8*x^2 + p9*x + p10

Coefficients:
p1 = -4.9267e-021
p2 = 8.8667e-018
p3 = -6.748e-015
p4 = 2.8325e-012
p5 = -7.1734e-010
p6 = 1.1249e-007
p7 = -1.094e-005
p8 = 0.00040036
p9 = 0.029408
p10 = -2.3221

Norm of residuals =
1.8811e-012

**Cascades236** · 08-19-09, 18:28

How different would a chart look with an optic mounted on a carry handle?

**nickdrak** · 08-20-09, 01:23

I dont get many chances to shoot out past 100yds locally, as most of my local ranges are limited to 25yds with one local PD range that has a 100yd rifle range.

Today I got to shoot at the National Guard range on their 300m pop-up range. The 100yds zero worked perfectly with consistent hits @ 300m.

The new Trijicon TR24G 1-4x help out a bunch, but the hold-offs were simple & fast at extended distances.

I still prefer the 100yd zero.