Need help zeroing AR iron sights

[hammAR]

Any and all help will be greatly appreciated - thanks!

...when you get tired of typing and reading let me know.......be glad to help.....

and don't buy that calculator...

.

[justaguy]

This is free.
http://www.eskimo.com/~jbm/calculations/traj/traj.html

Whatever you do dont let Ttoosie zero your AR. Make sure when you start everything is at "zero".


http://www.txmarks.org/cdfiles/Individu ... anship.pdf
Page 9-1
Chapter 9
Zeroing
To be combat effective, it is essential for the Marine to know how to zero his rifle. Zeroing is
adjusting the sights on the weapon to cause the shots to impact where the Marine aims. This
must be done while compensating for the effects of weather and the range to the target. It is
critical that Marines can zero their rifles and make the sight adjustments required to engage
targets accurately.
9001. Elements of Zeroing
There are five basic elements involved in zeroing a rifle: line of sight, point of aim, centerline of
the bore, trajectory, and range. See figure 9-1.
Figure 9-1. Elements of Zeroing.
a. Line of Sight. The line of sight is a straight line which begins at the center of the eye,
proceeds through the center of the rear sight aperture, and passes across the tip of the front sight
post to an aiming point on a target.
b. Aiming Point. The aiming point is the precise point where the tip of the front sight post is
placed in relationship to the target.
c. Centerline of the Bore. Centerline of the bore is an imaginary straight line beginning at the
chamber end of the barrel, proceeding out of the muzzle, and continuing indefinitely.
d. Trajectory. In flight, a bullet does not follow a straight line but travels in a curve or arc
which is called trajectory. Trajectory is the path a bullet travels to the target. As the bullet exits
the muzzle it travels on an upward path, intersecting the line of sight (because the sights are above
the muzzle). As the bullet travels farther, it begins to drop and intersects the line of sight again.
e. Range. Range is the known distance from the rifle to the target.
9002. Battlesight Zero (BZO)
BZO is the elevation and windage settings required to engage point targets from 0-300
yards/meters under ideal weather conditions (i.e., no wind). This means that the rifle sight are
adjusted so the bullet’s trajectory and the line of sight intersect at a range of 300 yards/meters.
When zeroing in windy conditions, the adjustments for windage to offset the effects of wind must
be removed to establish a BZO........

[justaguy]

.........Or skip all that ******** and let HammAR help you.

[jgalt]

...Whatever you do dont let Ttoosie zero your AR...

You know, the first thing I searched for was "How to zero your AR using a pipe wrench" - maybe that is why I couldn't find what I was looking for...

http://www.txmarks.org/cdfiles/Individual%20Weapons/MC%20Marksmanship.pdf

Thank you very much for the pdf - I will definitely set aside some time to read that over in the near future!

[sochr000]

as far as tools for the front sight post, either get HammAR to help you, or get one of these http://rrarms.com/catalog.php?prod=TL-9942.

You could use a small nail to adjust the front sight post, but without being there to show you how, it'd take some 'splaining I don't care to do over the interwebz.

[justaguy]

Do not buy a tool. For as much as you move your front site use a round. I really would take HammAR up on his offer it doesnt take that long, and you will learn a lot more.

[westberg]

Sights are over rated, you need to keep your eyes open for them to be effective. Someday when I have time I may give them a try............

[justaguy]

Sights are over rated, you need to keep your eyes open for them to be effective.

I was under the assumption everyone knew this.

[cobb]

It don't matter what you set your zero for if you can't see your sights. You said home defense weapon right?
Get yourself a set of night sights, then zero your rile: http://www.gunaccessories.com/ar15/AR15nightsights.asp

Not helpful - I've got what I've got right now, and need to make do with that right now. I will get some type of optic whenever I can afford to do so...

That's good, learn and get proficient with what you have. I am not a fan of lasers and I have proven that I can hit my intended target in low light without night sights. The question I have is, if it is too dark to see your non illuminated sights, are you still able to identify your target? If you are making sound shots, heck you don't need night sights to do that.

I downloaded "Ballistics Lite" for my Ipod touch.

Link? Or was it posted and I missed it? I wonder if that will work on a Blackberry?

[Stradawhovious]

For ballistics lite, check the apps store through your itunes program. That's where i got mine. It was free when I downloaded it.

[Fast351]

Most of the people I know who train have moved to a 100 yard zero, which puts you (I believe) at -3 at 300 yards, so you can shoot point of aim at anything 0-300 and be within 3 inches.

That said, for your intended use, 25, 50 or 100 yards zero makes very little difference. Any one of them will work.

There is a front sight tool for AR15s that works slick for pushing down the detent and spinning the sight at the same time. The same can be accomplished with a punch and a needle nose too.

If your bullet is hitting high, turn out the front sight, if it's hitting low, turn it in (works like a screw). Rear sight adjusts windage.

I usually zero at 25 yards, make the round hit 1" low, and that puts it on paper at 100 (usually a little high) and finish from there. You should be aware that if you do not have free float hand guards, and the barrel isn't a bull barrel, you will move the zero significantly by putting a sandbag under the handguard. I have a pencil barrel AR that moves more than 6" high at 100 using sandbags.

[nyffman]

Fast351, what you said about the sandbags under the handguard is something(more likely one of many things) that I haven't considered. How is that any different than supporting the gun with your hand from that point. And, how else would you support the front?

[plblark]

I have nothing to add to the discussion other than the observation that:

The Beauty of this board is the discussions and the occasional throw away nugget of wisdom that makes me sit back and go "Why is that? and what else does that teach me" quickly followed by the number of people jumping in to help answer those questions.

This is a great group for sure. Thanks.

[jgalt]

Fast351, what you said about the sandbags under the handguard is something(more likely one of many things) that I haven't considered. How is that any different than supporting the gun with your hand from that point. And, how else would you support the front?

I almost asked the same question but didn't. And now that I've read it the way you phrased it, I too am confused. What Fast351 must be saying is that any non-free floated barrel will never be able to be zeroed in with any real precision, as the vast majority of rifles with non-free floated barrels are held by the forward support hand on some type of hand guard, thereby putting pressure on the barrel. Basically, there is no way around it. The only way to get a precise zero is to either free float the barrel, or support the fore end somehow without touching the hand guard / barrel.

This is a logical conclusion arrived at solely based on what I've read here, i.e. I have no experience with these issues and may very well be wrong. I'm sure that one or more folks with some level of practical knowledge will correct me where I am wrong...

[nyffman]

Maybe I'll trying experimenting with a modified handgun type grip. If I can add some weight to stock, for balance, it should work, right?