Western Rifle Shooters Association

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Monday, February 11, 2008

Basic Rifle Marksmanship Series: Part II(A) - Open Sights



We'll continue with our Basic Rifle Marksmanship series, once you've gone back and reviewed Part I dealing with safety. We'll wait right here 'til you return.

You're back now, so let's begin. Because we want these lessons to be as useful as possible for a broad audience, we're going to start with the most common form of rifle sights - the so-called "open sights". The other major variant of iron rifle sights - aperture sights - we'll leave for Part II(B) of this series.

Fundamental sight theory requires the shooter to be aware of three discrete elements and their interrelationship:

1) the rear sight (the part in the diagram above that looks like a block "C" lying on its back);

2) the front sight (depicted in our diagram as the somewhat fuzzy post centered in the notch of the rear sight); and

3) the target (the fuzzy gray circle on top of the front sight, which is positioned as just touching the target at the 6 o'clock position).

This interrelationship is managed by the shooter by three concepts, to be performed in the following sequence for each shot:

A) Sight alignment: This term refers to the way the front and rear sights appear to the shooter after he or she has assumed the physical position to be used for the shot. Note that we are NOT talking about the sights themselves - after all, both the rear and front sights are attached mechanically to the rifle. Instead, what is really being analyzed under the label "sight alignment" is the alignment of the shooter's sighting eye with the sights themselves.

The question to be asked by the shooter is simply, "Am I positioned such that the front and rear sights appear in the same line as my eye?"

If so, we can move on to

B) Sight picture: First, take a look at the front and rear sights in our diagram and note how the front sight post is exactly centered in the nothch of the rear sight. Note also that the top of the front post is exactly the same height as the higher (non-notched) portions of the rear sight.

Both of these points (front sight post centered in notch and on the same level as the non-notched rear sight portions) are critically important. If the front post is more to the right, the bullet will hit to the right of your point of aim (POA); same idea (bullet strike to the left of POA) if the post is more to the left. Similarly, if the front post is higher or lower than the non-notched "ears" of the rear sight, your shot will go higher or lower, respectively, from your POA.

Make sense?

Just keep the front post centered in the notch and at the same height as the rear sight "ears", and you'll be fine.

C) Point of aim: Remember how I said that the shooter needed to keep three separate pieces in mind when using one's sights? We've been talking about two pieces (the front and rear sights), so let's add the third element now.

You'll see that in our diagram, the front and rear sights are aligned, and that the front post is centered and at the same level as the "ears".

So far, so good.

Now look at where the front post is placed relative to the target. If the target were an analog clock face, that position of low center would be where the "6" would be, right? That's why shooters refer to the sight picture in our diagram as a "six o'clock hold", since the POA is at the six o'clock position on the target.

In Part II(C) of this series, we'll talk about adjusting your sights mechanically to change where the bullet strikes (known as "point of impact", or "POI") for a given POA. For now, just assume that the sights on your rifle are adjusted to have the POI equal to the POA at the distance you are shooting.

POI=POA, ja?

The six o'clock hold gives beginners (and especially not-so-newcomers) a big advantage, in that it forces shooters to concentrate on the front sight post so that they can be sure that the target is just perched on the front post. That's where a more colorful name for the six o'clock hold - "pumpkin on a post"- started.

The key point to remember is that the human eye simply cannot focus with equal clarity on three distinct items located at varying distances from the eye - in other words, the rear sight, the front sight post, and the target itself. That issue being a fact of human biomechanics, the shooter must choose one item and let the others blur to a greater or lesser degree.

Which to choose?

Always choose the front sight post to be clear. It will be hard to discipline yourself at first - you and your eyes will want to try to focus on all three objects, or the target, or the rear sight, all at the same time. Take a deep breath and concentrate only on the front sight, and making sure that as you begin your trigger squeeze, that sharp front sight post stays right there, at the six o'clock position of the round (but somewhat fuzzy) bullseye target.

Say to yourself: "Sharp front sight, pumpkin on a post. Sharp front sight, pumpkin on a post."

Keep repeating that mantra, while allowing yourself only enough attention to the rear sight to ensure that your front post is still centered and on the same level as the "ears".

Do that on every shot, and you'll be a superstar. Promise!

To recap, successsful open rear sight usage comes down to proper sight alignment, the proper sight picture (maintained until the shot is fired) , and the proper point of aim for the target you are shooting.

Next time, we'll deal with the other major vaiety of iron sights - the "peep", or aperture, sight.

Thanks for coming around, and I hope you'll look forward to our next meeting as much as I will.

8 Comments:

Anonymous Anonymous said...

Thanks for the information.I haven't shot my Win 30-30 for almost 8 years and had forgotten all the basics on using open sights,but after reading this it all came back to me.Hopefully I will remember this when I get to go pig hunting in June 09.Thanks again Mark.Qld.Australia

May 7, 2009 at 12:17 AM  
Blogger CLAYTO said...

Thanks for the information.I have not fired my Win 30-30 for about 8 years and had forgotten all the basics that you just covered.I hope I can retain all of this when my next pig hunting trip comes up in June 09.Thanks Clayto.PS:When is the next series on adjusting open sights? Thanks again.

May 7, 2009 at 12:28 AM  
Anonymous Anonymous said...

Excellent information. At age 51, I purchased my 1st rifle (a spanish mauser .308 and love to shoot, However, no one has ever showed or explained the proper use of the sight. Next time I go to the range, I am going to bring a printed version of your instructions. I can see why my POA and POI are not the same, I have been using the sights (and especially my eyesight) all wrong.

July 24, 2009 at 5:31 AM  
Anonymous Anonymous said...

Good write up. I have one question concerning this sighting method. (This has been bothering me for a while...)

First, my assumption is that, with the top of the front sight placed at the 6 o'clock position of the target, the POI should be the center of the target, and not at the 6 o'clock.

So, if the target is 6-inches in diameter, then the POI should be 3-inches above the top of the front sight. However, if the target is 12-inches, then the POI should be 6-inches above, and so on.

How does this sighting method compensate for the different target sizes encountered in the field?

Again, thanks for the great write up!

March 1, 2010 at 9:08 PM  
Blogger Concerned American said...

Anon:

Assuming a constant point of aim, your actual point of impact will be whatever you manipulate your sighting equipment to achieve.

NRA highpower shooters adjust their sights so that a six o'clock POA achieves a centermass hit because the HP shooters want to be able to index their front sight just high enough to blot out all of the target white in the six o'clock hold.

Practical shooters adjust their POI to equal POA at the distance they expect to engage, and then know the ballistics of their load (along with their sighting equipment) to achieve results at different ranges using either hold-off or sight adjustments.

Make sense?

March 1, 2010 at 9:50 PM  
Anonymous Anonymous said...

Hey concerned, fantasic write up. Enjoyed it very much.

Have a question to throw at you. I own an sks, with adjustable front and rear sites. Rear site has a "slide" on it to adjust it...and front site just screws in and out to adjust Hight. I'm guessing the same principles apply to"siting in" the iron sites for this gun as others?

Also...distance perplexes me when it comes to sites. If I site my gun in to where I hit center at 50yds, then when the time comes that I need to hit something at 100yds, then I just mentally adjust? Keep front site on target, and lower rear site?

Thanks for the article.

November 5, 2010 at 5:43 PM  
Blogger Concerned American said...

Here's what I would do with an SKS:

1) Put the rear sight slider on 200 meters

2) Place my target at 25m

3) Fire 3-5 round groups at 25m; adjust windage and elevation so that point of aim = point of impact

4) Once POA = POI at 25m, move to 200 m and confirm zero, adjusting windage and elevation as needed to have 200m POA = 200m POI

5) When can, fire that load at 300, 400, & 500 yards to see how far you and your rifle can deliver rounds on a 20" square target.

See also this YouTube video

November 5, 2010 at 8:03 PM  
Blogger Concerned American said...

To follow-up, once you know where your rifle shoots with a 200m zero, I would not touch the sight. Change your POI by changing your aiming point by holding over at longer ranges.

Here's a ballistics chart for the 7.62x39 sks round and a 200-yard zero.

November 5, 2010 at 8:10 PM  

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