Advanced Marksmanship Perspective of Aim

[Sterling Shooter]

Is it possible to truly recognize a consistent perspective of aim when using a scope? What could be the magnitude of error for something short of a consistent perspective of aim when it appears there is no parallax error, the stock-weld feels consistent, and the sight picture is shadowless?

 

[Killswitch Engage]

Re: Perspective of Aim

you just listed all the pieces of repeatable and correct aim with an optic. what else is there? if you always glue your melon to the stock in the same spot, see the entire moon and paralax free. the only other thing i think is focusing on the cross hair and not the target just as you would the front sight post.

 

[Alan Warner]

Re: Perspective of Aim

Move your head rearward or the scope forward to allow the shadow ring and keep it concentric. Then there is no question, paralax is always correct.

Old Eyes

 

[BOLTRIPPER]

Re: Perspective of Aim

...........LUKE, feel the force...........

 

[Sterling Shooter]

Re: Perspective of Aim

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: BOLTRIPPER</div><div class="ubbcode-body">...........LUKE, feel the force...........</div></div>

Yeah, I know, perhaps, all the facts of good shooting are already known; yet, I wonder if the techniques used to appraise the presence of parallax are enough to detect it entirely.

 

[BOLTRIPPER]

Re: Perspective of Aim

if you are in a hurry and up against the clock and have not trained enough to be salty....or are a member of the un-washed , prolly no...

 

[Alan Warner]

Re: Perspective of Aim

a decent opic with a concentric perimeter ring will always be paralax free. the human eye/brain cannot detect paralax error in a still sighting state with full field.

Ya'll can just go take a flying f--- at the moon otherwise.

I have not busted a cap in over twelve months. Any of you want to meet up and go $100 a shot for 100 rounds on a KD range? Two sighters.

 

[DMS]

Re: Perspective of Aim

Old Eyes:
How about I send you the match bulletin from the last match we shot together and you send me the $100? We'll forget about the other 3 points. If it would make you feel better I did it using one of your sights.

 

[Sterling Shooter]

Re: Perspective of Aim

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Old Eyes</div><div class="ubbcode-body">Move your head rearward or the scope forward to allow the shadow ring and keep it concentric. Then there is no question, paralax is always correct.

Old Eyes</div></div>

You intentionally create a shadow ring? I guess it's the shadow which then becomes the reference to indicate when indeed the eye is in a consistent relationship with the scope. Well, now, knowing that, I think I get it. Thanks for the sincere tone too.

 

[9H_Cracka]

Re: Perspective of Aim

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Sterling Shooter</div><div class="ubbcode-body">

You intentionally create a shadow ring? </div></div>

Absolutely.

 

[Sterling Shooter]

Re: Perspective of Aim

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: NineHotel</div><div class="ubbcode-body"><div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Sterling Shooter</div><div class="ubbcode-body">

You intentionally create a shadow ring? </div></div>

Absolutely.</div></div>

Do you recall the source of knowledge?

 

[Greg Langelius *]

Re: Perspective of Aim

Back when there was such a thing as Black Thoughts, I can remember floating that little crumb upon these local waters.

While it works, it's something I considered to be a last ditch effort to deal with poor parallax correction. I'd rather adjust it out than deal with issues that artificially diminish the relative diameter of the exit pupil image. Even if I can't adjust it out, quartering the reticle works as well, if not as quickly, as overall shadowing.

Shadowing and quartering are simply two somewhat different methods of aligning the exit pupil and the iris.

Greg

 

[9H_Cracka]

Re: Perspective of Aim

I came to it on my own Skip. With USO scopes due to the overall length of the scope the lenses are pretty flat therefore they are not real critical as far as needing to adjust the parallax control to obtain decent target focus. I leave mine at 400 most of the time then use the shadow to make sure I'm lined up with the same head position. It is basically like shooting an aperture rear sight, and I do this automatically with the aperture sight since I shoot them 4-7 times a week, so setting the scope up so I have a similar reference point makes it an automatic task to have zero parallax.

To Greg's point, if I think I need more field of view I turn the power down. I don't know if FOV and exit pupil are directly related or not.

 

[Sterling Shooter]

Re: Perspective of Aim

9H,

I'm going to try this out.

 

[1SMALLJOHNSON]

Re: Perspective of Aim

You guys might want to try this. I use it all the time when I'm teaching a newby how to look thru a scope. I'm amazed that many folks just can't see thru a tube! Anyway:

Unload the gun, take out the bolt
Have the shooter place their eye behind the scope.
You position yourself in front of the scope.
Look back thru the exit pupil
You'll see some portion of the shooters face
Tell them where to move their eye so that you can see their eye centered in the scope and the blurry cross-hairs.
When they're "on it", move your head quickly away and let them see what they're supposed to see. Works every time!

Now, relating to the shadow ring: Do the same exercise, but have the shooters eye at the wrong distance for optimized vision. Get them centered up. See if the ghost ring appears concentric and centered for them. If it does, the ghost ring concept proves viable. I can tell you that I use it, and it seems to work well for me.

 

[Greg Langelius *]

Re: Perspective of Aim

I think we all need to back off a tad before we get wrapped around an axle.

I could be wrong about this, but my understanding is that parallax is a consequence of refraction. Consequently, where there is no refraction, I'm making a SWAG that there is no parallax. Iron sights function without refraction, it is when lenses are incorporated that refraction becomes an issue.

I have never heard of the term 'perspective of aim' anywhere but as part of these discussions here on The 'Hide.

So I sit here, waiting to be educated.

Greg

 

[j-huskey]

Re: Perspective of Aim

The technique has been proven to work elsewhere and long before.

The Brits taught it with some of the weird sitting positions used in the mountains when they had to improvise.
We used it in some overseas competitions where they forced you to use the wierd positions and it worked for us very well.
The old Sniper's Paradise shoots made you use this in some stages, most specific, the roll-over prone where you shoot the rifle sideways under a car, etc.

As long as the eye is centered, the black ring (shadow) around the scope is equal, or there is no ring, it's all the same.

The ONLY thing changed with these techniques is the quality of the sight picture, the further back you are from the scope, the fuzzier the sight picture, that's all.

 

[Sterling Shooter]

Re: Perspective of Aim

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Greg Langelius *</div><div class="ubbcode-body">

I have never heard of the term 'perspective of aim' anywhere but as part of these discussions here on The 'Hide.



Greg</div></div>

Perspective of aim is mentioned in some recent USAMU SDM and BRM curriculum. But, whether you've heard of it or not, everybody has a perspective of where the gun is pointed, even if the gun's sights are not being used, as in instinctive shooting. Perspective of aim is correct when it coinsides with where the gun is pointed.

 

[9H_Cracka]

Re: Perspective of Aim

Both the Army Field Manual and the Guidebook for Marines show the effect of not having the front sight centered in the rear aperture. Both Marine and Army sniper books show the same for scopes as it relates to head position with an optic. To say that parallax errors are confined to optics may be a focus on semantics or word choice rather than the fundamentals of marksmanship.

 

[CoryT]

Re: Perspective of Aim

Parallax is confined to optical sights. Parallax errors occur when the reticle and the target are not in the same focal plane. If you then misalign your eye behind the scope, there will be some angular error between the reticle and the target. From tests I've done, about the maximum parallax error one can have without obvious signs of a problem (large cresent shaped field, or blurry image) is about 1/4 MOA. You can see the amount of parallax error by setting the focus a bit off, then moving around behind the scope. Either the target or reticle will appear to shift, depending on your focal point, as you move around behind the scope. The amount of movement is the amount of parallax. Parallax rarely causes a signifigant problem. Most fixed focus scopes are set to be paralax free at 150 yards, but no one seem to have a major problem shooting them at 1000.

Not centering the front sight in the rear apeture is a sight alignment problem, which has nothing at all to do with parallax. Optics all but eliminate sight alignment issues, if you see a complete field you are good to go. Some systems, like the Aimpoint, are in fact parallax free, as the image and reticle are projected on the same glass surface.

The major advantage of an optical sight is the practial elimination of one of the three keys items, Sight Alignment, Sight Picture and Trigger Control.

 

[The Mechanic]

Re: Perspective of Aim

I have always "made the ring" on a scope to start that always assured me I would not get an eyebrow smiley and made sure I was straight behind the rifle. Got into the habit long ago when using irons on the HK with a ring of light around the front sight.

 

[Greg Langelius *]

Re: Perspective of Aim

Thank you all, I am now considerably more educated.

Greg

 

[chuff]

Re: Perspective of Aim

I have to thank everyone that contributed to this thread. I went to the range today and put some of this info into practice with some very pleasing results. Now if I could just get the rest of my shooting skills straightened out......

 

[Sterling Shooter]

Re: Perspective of Aim

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: chuff</div><div class="ubbcode-body">I have to thank everyone that contributed to this thread. I went to the range today and put some of this info into practice with some very pleasing results. Now if I could just get the rest of my shooting skills straightened out......</div></div>

I'm glad someone here is benefiting from the dialog. I too went to the range yesterday. It was my first practice session since last November. I thought the range would be empty, but, with good weather, every shooting point had a shooter, mostly, folks shooting black rifles from the bench.

These folks, all of 'em, knew how to shoot, but, didn't know how to shoot. That's to say, they could execute the firing task, but, didn't know, it appeared, to know anything about marksmanship.

No doubt, everyone seemed to be having a good time, yet, I don't believe this is what Teddy Roosevelt was thinking when he talked about "a nation of marksmen". It was somewhat a bittersweet experience.

At any rate, I think, as curious as you are, you're on your way to becoming an extraordinary marksman.

 

[Greg Langelius *]

Re: Perspective of Aim

A Nation of Marksmen is that curiously unique phenomenon, the self-endangered species.

 

[Sterling Shooter]

Re: Perspective of Aim

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Greg Langelius *</div><div class="ubbcode-body">A Nation of Marksmen is that curiously unique phenomenon, the self-endangered species.</div></div>

Greg,

You've never been at a loss for words, details please, I'm not sure I know what you mean.

 

[Sean the Nailer]

Re: Perspective of Aim

As I'm always interested in 'doing things right' as well as freely admitting that 'there's always more to learn', thanks for this guys.

 

[Greg Langelius *]

Re: Perspective of Aim

.