Educate the moron about sight zeroing?

[powermad]

Having recently joined the AR15 club I went searching for iron sight/RD zero..
Wow.. 25/300m, , 36/300 yards, 50/200 yards and 100 yards.

Ballistic calculators are handy and fun to play with to see how the trajectory changes.
After playing around with one for a while I found that a 100 yd zero is good for up to 100 yds point and shoot and a 50 yd zero for up to 200 yds point and shoot with xm193 ammo.

Graphs helped me see the trajectory a bit better as well and where to put the "tube" for my use.

Not mine...

For me it looks like the 100 yd zero would work well as most of my shooting is in the 100 yd range.
For the occasional 200 yd shot it looks like it's 2.4" low, which isn't much of a hold over at that distance. One click is easy enough to remember and put back if you want to dial it in.

 

[Diamondback]

So according to this ballistic calculator I found: JBM - Calculations - Trajectory
MPBR based on Mk 262 running around 2363fps with a 5" "vitals radius" is 288yd, recommended zero 247--this looks like a 25/250 is "close enough". Worrying part is I drop below Mk 262's frag velocity at only 50yd... at 288 I only get 1730.

Looks like time to forget about a briefcase-size sniper-buster and focus on the CQB side instead... it's hard to see Imminent Jeopardy at much beyond 50yds in even Chiraq or Hell A.

 

[Who The F R U]

20''
2 click's back/down from 8/3 zero at 25. return to 8/3.

14.5''
2 click's back/down from 5/3 zero at 25. return to 5/3, same on commando 11.5'' or 10.5''.

Two week class for pouges.

ANY issue AR my zero is up 4 right 2 with irons.

LRRP's out..........................

 

[ConcernedCitizen]

50/200 yard zero for me, and my 10.5" pistol was hitting steel at 200 pretty easily during the Brown's Camp cleanup/shoot.

I adjust iron sights the same, unless they're designed for easy elevation adjustment.

For my detachable carry handles, I use the RIBZ method to sight in for 50/200, but still have the 300-600 elevation work as intended.

If you're serious about wanting to shoot past 300 yards with this pistol, consider a LPVO instead of a red dot. A 1-4x or 1-6x scope will still be fast enough close in, but will be much better than just a red dot for longer range.

 

[EPS]

36 Yards
That will get you a little bit low at close RANGE .
And the difference between high and low will only be about 8 inches out to around 200

 

[Geardo]

Thanks, guys. @Ura-Ki No magnifier on this, it's a Bugout Bag/Briefcase Carry rig and volume and getting smacked around are already concerns. While I'd really LIKE to have some "counter-Vegas-type shooter" capacity, the primary mission is CQB and Active Shooter Response. The whackjob in Florida would be Primary Target, the scumbag in Vegas Secondary.

Preferred ammo... well, I'm looking at 62-64gr Gold Dots along with SOST and Mk 262, but I've yet to find any ballistics tables for those out of a 10.3. I don't think Hornady Interlock SBR made the Doc Roberts List...

Suppressed 5.56 SBR Velocity Tests--41 Factory Loads from 10.5", 11.5", 12.5" & 14.5" ALL DONE! - Page 1 - AR15.COM

 

[etrain16]

Good thread. I've been on the 50-yard zero bandwagon for a bit, but looking at the 36-yard, it's got me re-thinking things. Some great, informative responses from you folks here!

 

[BillM]

Chart for xm 193 out of a 10.3' barrel, 200 yd zero. That's 1/2" high at 50, keeps you within
2" high or low out to around 230. Found several references to 2650-2700 for velocity out of a 10.3, YMMV.

Drag Function: G1
Ballistic Coefficient: 0.243
Bullet Weight: 55 gr
Initial Velocity: 2650 fps
Sight Height : 2.5 in
Shooting Angle: 0° Wind Speed: 10 mph
Wind Angle: 90°
Zero Range: 200 yd
Chart Range: 460 yd
Maximum Range: 3565 yd
Step Size: 25 yd
International Standard Atmosphere
Altitude: Sea Level (0 ft)
Barometric Pressure: 29.92 Hg
Temperature: 59° F
Relative Humidity: 50%
Speed of Sound: 1116 fps

Range Elevation Elevation Elevation Windage Windage Windage Time Energy Vel[x+y]
(yd) (in) (MOA) (MIL) (in) (MOA) (MIL) (s) (ft.lbf) (ft/s)
0 -2.50 0.00 0.00 0.03 0.00 0.00 0.00 858 2650
25 -0.82 3.12 0.91 0.12 0.47 0.14 0.03 799 2558
50 0.51 -0.98 -0.28 0.40 0.75 0.22 0.06 745 2469
75 1.49 -1.89 -0.55 0.86 1.09 0.32 0.09 693 2381
100 2.08 -1.99 -0.58 1.53 1.46 0.42 0.12 644 2295
125 2.27 -1.73 -0.50 2.41 1.84 0.53 0.16 597 2211
150 2.00 -1.27 -0.37 3.51 2.23 0.65 0.19 554 2129
175 1.26 -0.69 -0.20 4.85 2.65 0.77 0.23 512 2048
200 0.00 0.00 0.00 6.45 3.08 0.89 0.26 474 1969
225 -1.82 0.77 0.22 8.30 3.52 1.02 0.30 437 1892
250 -4.25 1.62 0.47 10.44 3.99 1.16 0.34 403 1817
275 -7.34 2.55 0.74 12.88 4.47 1.30 0.38 372 1744
300 -11.14 3.54 1.03 15.62 4.97 1.45 0.43 342 1674
325 -15.72 4.62 1.34 18.70 5.49 1.60 0.47 315 1606
350 -21.14 5.77 1.68 22.11 6.03 1.75 0.52 290 1540
375 -27.48 6.99 2.03 25.88 6.59 1.92 0.57 266 1477
400 -34.81 8.31 2.42 30.03 7.17 2.08 0.62 245 1417
425 -43.23 9.71 2.82 34.56 7.76 2.26 0.68 226 1360
450 -52.82 11.21 3.26 39.49 8.38 2.44 0.73 208 1306

 

[EPS]

Chart for xm 193 out of a 10.3' barrel, 200 yd zero. That's 1/2" high at 50, keeps you within
2" high or low out to around 230. Found several references to 2650-2700 for velocity out of a 10.3, YMMV.

Drag Function: G1
Ballistic Coefficient: 0.243
Bullet Weight: 55 gr
Initial Velocity: 2650 fps
Sight Height : 2.5 in
Shooting Angle: 0° Wind Speed: 10 mph
Wind Angle: 90°
Zero Range: 200 yd
Chart Range: 460 yd
Maximum Range: 3565 yd
Step Size: 25 yd
International Standard Atmosphere
Altitude: Sea Level (0 ft)
Barometric Pressure: 29.92 Hg
Temperature: 59° F
Relative Humidity: 50%
Speed of Sound: 1116 fps

Range Elevation Elevation Elevation Windage Windage Windage Time Energy Vel[x+y]
(yd) (in) (MOA) (MIL) (in) (MOA) (MIL) (s) (ft.lbf) (ft/s)
0 -2.50 0.00 0.00 0.03 0.00 0.00 0.00 858 2650
25 -0.82 3.12 0.91 0.12 0.47 0.14 0.03 799 2558
50 0.51 -0.98 -0.28 0.40 0.75 0.22 0.06 745 2469
75 1.49 -1.89 -0.55 0.86 1.09 0.32 0.09 693 2381
100 2.08 -1.99 -0.58 1.53 1.46 0.42 0.12 644 2295
125 2.27 -1.73 -0.50 2.41 1.84 0.53 0.16 597 2211
150 2.00 -1.27 -0.37 3.51 2.23 0.65 0.19 554 2129
175 1.26 -0.69 -0.20 4.85 2.65 0.77 0.23 512 2048
200 0.00 0.00 0.00 6.45 3.08 0.89 0.26 474 1969
225 -1.82 0.77 0.22 8.30 3.52 1.02 0.30 437 1892
250 -4.25 1.62 0.47 10.44 3.99 1.16 0.34 403 1817
275 -7.34 2.55 0.74 12.88 4.47 1.30 0.38 372 1744
300 -11.14 3.54 1.03 15.62 4.97 1.45 0.43 342 1674
325 -15.72 4.62 1.34 18.70 5.49 1.60 0.47 315 1606
350 -21.14 5.77 1.68 22.11 6.03 1.75 0.52 290 1540
375 -27.48 6.99 2.03 25.88 6.59 1.92 0.57 266 1477
400 -34.81 8.31 2.42 30.03 7.17 2.08 0.62 245 1417
425 -43.23 9.71 2.82 34.56 7.76 2.26 0.68 226 1360
450 -52.82 11.21 3.26 39.49 8.38 2.44 0.73 208 1306

Holy $#!+ Man all those numbers give me a headache .and I just started drinking.
Unless you're actually Shooting for bulls eye every time .36 Yards is a standard quick zero for a combat gun with a red dot or open sites.
Obviously with in 36 Yards you will be low .
The difference between the muzzle and the top of your site.about 4 inch.and past 36 Yards it will be shooting high out to about 200 Yards then it will start to drop again.

 

[EPS]

And if you want to hit the bull's eye every shot .
Get a SCOPE that has a adjustable windage and vertical adjustable on the fly site it for 100 out to 1000 just turn the thing form zero to 10.
Zero would be 100 yards and 10 would be 1000 Yards

 

[ConcernedCitizen]

The reason I prefer a 50 yard zero is because it never rises more than ~2" above the POA. With a 36 yard zero, you are approximately 5" above POA at the mid-point, and a traditional 300m military zero puts you 6" above POA.

I don't like the thought of putting a shot over a target, and I hate worrying about when to hold low and when to hold high.

With a 50 yard zero, I'm +/- 2" out to 250 yards while holding dead on, and then only need to hold over from there. Here are some charts to help illustrate:



The top chart is for a 20" barrel, and the bottom chart is 16". These will change a bit based on barrel length and velocity, but not too much. The basic principle is still the same.

This is why I favor the 50/200 yard zero.

 

[EPS]

The reason I prefer a 50 yard zero is because it never rises more than ~2" above the POA. With a 36 yard zero, you are approximately 5" above POA at the mid-point, and a traditional 300m military zero puts you 6" above POA.

I don't like the thought of putting a shot over a target, and I hate worrying about when to hold low and when to hold high.

With a 50 yard zero, I'm +/- 2" out to 250 yards while holding dead on, and then only need to hold over from there. Here are some charts to help illustrate:

View attachment 495902 View attachment 495903

The top chart is for a 20" barrel, and the bottom chart is 16". These will change a bit based on barrel length and velocity, but not too much. The basic principle is still the same.

This is why I favor the 50/200 yard zero.

That's fine I know lots of people that do the 50 Yard zero .
But the way I was told was 36 Yards that's the easiest way to do it you can do a 36 Yards zero at a indoor range pretty much.
The fact is .
Unless you're actually in a war zone if you shoot some one beyond that it's murder.
But if the guy is on the side walk in front of your house Shooting at you .
Most houses are 35 YARDS or less from the street why site you gun out to 300 Yards unless you're doing long range Shooting

 

[EPS]

Hell I can break out my one RIFLE dial the SCOPE to 800 and stop a robbery at the gas station down the street .
But guess who's going to jail .
Me lol .
And guess who gets a ride in the corner van.
But that doesn't matter .I'm still in jail for murder

 

[ConcernedCitizen]

That's fine I know lots of people that do the 50 Yard zero .
But the way I was told was 36 Yards that's the easiest way to do it you can do a 36 Yards zero at a indoor range pretty much.
The fact is .
Unless you're actually in a war zone if you shoot some one beyond that it's murder.
But if the guy is on the side walk in front of your house Shooting at you .
Most houses are 35 YARDS or less from the street why site you gun out to 300 Yards unless you're doing long range Shooting

The problem is that a 36 yard zero essentially is a 300 yard zero! At the midpoint, around 175 yards, you are hitting 5" above POA.

My rifles are multipurpose, and are more likely to be used on small to medium sized critters, and hopefully never used on 2-legged varmints.

For hunting or pest control, 5-6" high could go right over the target or miss the vitals, where 1-2" high should still be a good shot.

Everyone is entitled to run what they are comfortable with; I'm just trying to explain the reasoning behind my personal choice.

 

[EPS]

The problem is that a 36 yard zero essentially is a 300 yard zero! At the midpoint, around 175 yards, you are hitting 5" above POA.

My rifles are multipurpose, and are more likely to be used on small to medium sized critters, and hopefully never used on 2-legged varmints.

For hunting or pest control, 5-6" high could go right over the target or miss the vitals, where 1-2" high should still be a good shot.

Everyone is entitled to run what they are comfortable with; I'm just trying to explain the reasoning behind my personal choice.

Well that's true the gun that I have that can shoot that far is only for critters .lol for now
But I believe he wanted a basic quick site in .
The basic is 36 Yards .
Or anything between 36 and 50 should do just fine .
Because the last I checked you can't hunt critters with a 5.56 .
Unless there the dope head USELESS POS.
THAT PARKED THERE MOTORHOME ON YOUR STREET AND IS STEALING ALL YOUR $#!+.
WHEN YOU GO TO WORK.!

 

[ConcernedCitizen]

At 36 yards, a 50 yard zero will be about 3/4" low. Either one will work just fine at that distance!

Here in Oregon, we can legally hunt deer and cougar with a .223, and they're also useful against any farm pests such as coyotes and porcupines. They're a good general purpose rifle!

 

[Diamondback]

Okay, let me pitch in my own intent: The design-concept role for my build is a PDW for Homestead D and for Active Shooter Response--whether single or multiperp, a tool specifically meant to RSVP "not in this lifetime for me or anyone around me" as soon as the scumbags send out their murderparty "invitations."

 

[EPS]

Okay, let me pitch in my own intent: The design-concept role for my build is a PDW for Homestead D and for Active Shooter Response--whether single or multiperp, a tool specifically meant to RSVP "not in this lifetime for me or anyone around me" as soon as the scumbags send out their murderparty "invitations."

36 Yards

 

[ConcernedCitizen]

Okay, let me pitch in my own intent: The design-concept role for my build is a PDW for Homestead D and for Active Shooter Response--whether single or multiperp, a tool specifically meant to RSVP "not in this lifetime for me or anyone around me" as soon as the scumbags send out their murderparty "invitations."

I still say if you really want to be effective at 300+ yards, you should try a 1-4x or 1-6x LPVO.

It's almost as fast as a red dot on 1x, and magnification is always good for longer shots! The only drawback is battery life compared to a good red dot.

If you're located in the PDX area, I'd be more than happy to let you try out a few different options to help see what works best for you.

 

[Diamondback]

@ConcernedCitizen Unfortunately, I'm up by Seattle and not very mobile--long-range is secondary to the "knife fight" since few rounds offer acceptable terminal ballistics from this barrel beyond about 50yd, and the current optic was chosen specifically for being friendly to failing eyes like mine. If I was building a true clone Mk 18, I'd probably be right with you and go LPVO assuming I could find one suitable for getting smacked around in a briefcase all day.

To give you an idea of the area we're talking about for "home", the entire cul-de-sac loop I'm working on getting my mother and myself moved onto, including all the properties on the outside around it, could fit onto the astroturf at CenturyLink Stadium.