I may be at the last thing to try. I have a vision problem. Wearing corrective lens spectacles, my best non-optical rifle aiming accuracy occurs when the bifocal corrects for intermediate (computer screen) distance and far distance. With this arrangement I have eliminated my problem seeing handgun sights and shooting accurately at handgun hunting distances. My head is more or less upright for this shooting.
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While I do not shoot single-shot rifles, my best bet to query people experienced with an aperture front sight should be with long-range single-shot match shooters.

When rifle shooting, my head is positioned that I see front sight (and target) in the top inside sixth of my lens. In this position I see the target clearly but see only a hazy blur that is the front sight.

Aiming through an aperture rear sight, it makes no difference in acuity of front sight blade whether the barrel length is 16.25 inches or 26 inches. I will not use a barrel longer than 26 inches with one of my lever action rifles.

Last week I went shooting with a friend who brought a C. Sharps 45-70 target rifle. His front sight was not a blade; it was a tiny aperture.

Finally, to the question: Would a front sight-as-aperture function similarly to a rear aperture sight -- that is, will my brain automatically center my point of aim within its tiny front "hole?" If the front sight functions as I just described, my inability to focus on the sight, as an aiming point, becomes irrelevant.

last week i was at klm firearms in seguin, tx... i saw the blaser 93 stutzen rifle.... the open sights are differnt from anything i'd ever seen before... sight radius is maybe 12"... rear sight is about where the end of the fore-arm would be, had it not been a mannlicher-style stock... phil made the remark that it was earier for old eyes to focus there...or maybe it was to clear a scope... anyway, i could see (and focus on) both front and rear sights, without much trouble.... something to think about....

You are not alone in your vision problems. I had a pair of glasses made with an intermediate focus for my master eye and a distance focus for my other eye. I also included a slight yellow tint to boost contrast. Since I shoot with both eyes open... It works for me. I would try the type of irons with a peep front and rear and then use only my distance glasses. Or scopes which I require reading glasses to ficus well ... it's tough getting old.

quote:

Originally posted by Naphtali:

Finally, to the question: Would a front sight-as-aperture function similarly to a rear aperture sight -- that is, will my brain automatically center my point of aim within its tiny front "hole?" If the front sight functions as I just described, my inability to focus on the sight, as an aiming point, becomes irrelevant.

Yes, and No.

The hardest thing to teach shooters just learning to shoot a front aperture sight is to use a large enough aperture. Most, rather than listening to instruction and learning how to use it, insist on imposing their own habits and counter-productive intuition onto the situation....forcing themselves to peer through a tiny aperture.

That seldom works well for most shooters(some do seem to manage it). The reason it doesn't work easily is that if the aperture is too small, they need to look very carefully at (and focus on) whether the target is tending to "melt" into one side or the other of the inside of the aperture.

For the front aperture to work as you have indicated, it needs to have a large, clear, band of light all the way around the target when the target is seen through the front aperture. Then the eye WILL automatically center it, because the eye will automatically pick up any peripheral reduction in the size of the band of light on one side or top or bottom, and act to even it up on all sides.

Having said that, it remains better for most if one does have the eyesight to do so, to focus on the front sight, whether aperture or post. As suggested earlier in this thread, an infinitely variable rear aperture similar to a Merit Master sight will allow one to do that.

Since adjusting spectacles' prescription, I have no significant problem shooting handguns.

When rifle shooting, I presently use an adjustable aperture rear -- I own frame-mounted units and have tried tang-mounted. I own a muzzleloader with 32-inch barrel that mounts a Lyman adjustable rear sight and a Lyman 17 target front. I have used in the 17 the thinnest blade insert available mounted upside down. I tested this arrangement again yesterday. Bupkes! Front blade is extremely fuzzy. I then swapped it out for the smallest aperture insert, again mounted upside down. I was unable to see any outline of the front aperture -- just fuzz. I was also unable to see the target clearly. Did I insert too small an aperture front?

I have not yet tried a rear diopter-adjustable aperture or the largest of my aperture inserts. Regarding futzing with the rear aperture, since I have no trouble seeing through it, why will adjusting its aperture diameter will render a blade or aperture front sight in sharp focus?

Since this appears to be a problem far-sighted shooters might have, because my prescription causes me to use my distance vision bifocal, there must be a solution.

I have not yet queried my ophthalmologist about isolating the top inside sixth or eighth of sighting eye's lens with a different prescription, this lens being a bizarre bifocal/trifocal.
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I have tried Zeiss Gradal Top progressive lenses unsuccessfully. I will not use contact lenses under any circumstance. And I doubt ophthalmic surgery would correct all multiple dysfunctions.

I really don't want to use an Ultradot L/T red dot sight, but it is small, non-magnifying, and less of an aesthetic eyesore than most optical sights.

quote:

Originally posted by Naphtali:
Since adjusting spectacles' prescription, I have no significant problem shooting handguns.

When rifle shooting, I presently use an adjustable aperture rear -- I own frame-mounted units and have tried tang-mounted. I own a muzzleloader with 32-inch barrel that mounts a Lyman adjustable rear sight and a Lyman 17 target front. I have used in the 17 the thinnest blade insert available mounted upside down. I tested this arrangement again yesterday. Bupkes! Front blade is extremely fuzzy. I then swapped it out for the smallest aperture insert, again mounted upside down. I was unable to see any outline of the front aperture -- just fuzz. I was also unable to see the target clearly. Did I insert too small an aperture front?

I have not yet tried a rear diopter-adjustable aperture or the largest of my aperture inserts. Regarding futzing with the rear aperture, since I have no trouble seeing through it, why will adjusting its aperture diameter will render a blade or aperture front sight in sharp focus?

Since this appears to be a problem far-sighted shooters might have, because my prescription causes me to use my distance vision bifocal, there must be a solution.

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My guess would be that you are using too large a rear aperture. That will shorten the depth of field your eye can see sharply, just like any camera lens diaphragm which is opened too wide would "fuzz" a picture of an object. That will only be made worse by a pair of glasses which is ground to provide clearest vision at short distances from the eye such as is encountered with pistol sights.

You don't necessarily want a TINY rear aperture, just one small enough to sharpen your vision over a longer depth of field, so the learly visible area includes the front sight.

Think back to the times you visited your eye doc. Did he/she ever have you close one eye and hold a paddle with a bunch of little holes in it in front of your open eye? Did you find that by moving the paddle around and looking through the varous holes in it that you finally found one which brought the eye test chart into clear focus? What you were doing was trying different size apertures until you found one which made your vision most sharp at the exact distance the eye chart was from you.

Now you need to do the same thing until you find an aperture which makes the front sight most clearly visible at the distance it is from your eye when you are shooting your rifle.

Rather than buy a ton of fixed rear sight apertures and experimient with all of them, the easiest way is to buy an infinitely variable rear aperture (again like the Merit Master aperture), and use it. It is almost instantly adjustable just by turning it with your hand, and is used by the great majority of iron sight hi-power competitors in this country.

If you do choose to use a fixed reticule, just remember that your vision changes constantly during every day as fluid builds up and/or decreases in your eyes, and as the ambient light level changes and the iris of your eye dilates or contracts. So, a fixed aperture which might work well this morning may not this afternoon. Again, the advantage is to the adjustable aperture.

I use a bolt action .22LR target rifle with aperatures front and rear. With a 25" barrel, the sighting radius is close to 30". What I do is focus on the target, looking through the sights but not really seeing them. The effect is just like looking down the bore or a piece of pipe - there is no awareness of space between the sights, and very little awareness of space between the front sight and the target.

If I can see the target, I'm on it, at least close enough for .22 siloutte shooting.

I shall try to impose upon my friend with the Sharps BP target rifle to see if I can see (forgive me) using a variety of [aperture] front and rear sight apertures. All it takes is one workable set.

And the consensus is to use smaller rear aperture and larger front one for the first test?

quote:

"that is, will my brain automatically center my point of aim within its tiny front "hole?" If the front sight functions as I just described, my inability to focus on the sight, as an aiming point, becomes irrelevant".

I believe it would function as you state. The "globe" or aperture front sight is excellent for bullseye shooting, as all one need do is keep an equal amount of "white" around the bull and squeeze. Since the eye will always seek the point of strongest light, the shooter will be looking thru the center of both the front & rear aperture.
(I too have a ML with a Lyman adjustable aoperture on the rear sught & a Lyman #17 on the front. It works great for target shooting with the aperture in the front sight. But for hunting purposes, I always remove the #17 front and replace it with a nice shiny Sourdough front sight that has the brass 45-degree insert in the rear facew of the blade. Even if the front blade is "fuzzy", that insert is visible. Just put it on the buck's shoulder and touch the front trigger.)

HOWEVER: The aperture front sight is extremely poor for hunting purposes. It tends to block one's view of the target, and all you see of the quarry is a brown or grey mass, giving you no idea of which part of the critter's anatomy you are seeing thru the two apertures!

quote:

Originally posted by jimatcat:
last week i was at klm firearms in seguin, tx... i saw the blaser 93 stutzen rifle.... the open sights are differnt from anything i'd ever seen before... sight radius is maybe 12"... rear sight is about where the end of the fore-arm would be, had it not been a mannlicher-style stock... phil made the remark that it was earier for old eyes to focus there...or maybe it was to clear a scope... anyway, i could see (and focus on) both front and rear sights, without much trouble.... something to think about....

I believe that sight arrangement is called a "battue" sight system or some such name. It appears to be quite popular in Europe for fast shooting at close-range, fast targets such as wildeschwein in forest settings. I would not use such a setup. For one thing, the sight radius is too short for any precision shooting.

Unscrew the peep and use the threaded hole..then just look through the hole and put the front sight on the target and pull the trigger..Your eye will automatically center the front sight.

In other words look through the hole and forget you even have a rear sight and just put the front sight on your target. It is the fastest sight known to man, and very accurate to 200 yards and with practice 300 yards is very doable

grenadier has it right.
having shot competative archery for a number of years and wear glasses, i have had a set of glasses ground with the correction in the upeer left corner of my right lense. i literally took my target bow into the optomatrists office, and he marked the lense where i was looking through with my bow at full draw as if i were shooting.
as for front appertures, we shoot with a front aperture, the scope on our bow. some guys use a dot on the lense as the aimpoint some use a ring about a 1/4 inch in diameter( just a touch bigger than the "X" ring on the bullseye), that's what i use. we use the peep size to to tune clarity of the sight picture, changing size according to light conditions and scope magnification.
you get so used to focusing on the "Xring" with the ring on the lense surrounding it that when you use a scope with the dot on the lense, you find that you can't settle down on the sight picture because you are constantly moving the dot out of the way to see the "x ring".

A smaller rear aperture helps with depth of field-ability to see better downrange, and somewhat clearer focus on the front post. Too small, and you lose brightness.

As an avid High Power competitor, I use an M1 Garand with a .052 rear aperture with a .5 diopter insert lens (Bjones sights) and a medium sized front post-standard is .085, NM is .062, I use one ground to .074. My spectacles are designed for optimum long distance vision, with a bifocal for up-close/reading stuff, I could get a dedicated shooting prescription, but I am not a big spender, plus I'd probably stumble around after forgettting to take them off and put on regular specs.

For hunting, I use opens sights (larger ivory bead seems to work well, compared to a post) with the rear positioned as far forward as I can-sight radius on my 416 Rigby No. 1 is only 14", which helps being able to see the shallow V and the bead quite well, and I am confident of using it out to 150 yds or so-killed a nice Doe last fall with it at a measured 145 yds and obtained a clean high heart kill.

I use regular regular spectacles-hunting ain't target shooting, the boiler room of most big game is at least 10-10 inches, while the X ring at 200 yards is ~2" in diameter. Also, I use a low powered variable (Burris 2-7x) seems just right for all of my needs so far) to help with my presbyopia.

God Bless

Good info to be found at BJonessights.com, shootingsight.com....

God Bless

The optimum rear aperture will vary with your vision and the ambient light. If I use the smallest rear aperture I get an out of round picture thanks to my aging eyesight.
In the middle of the day my usual aperture is too bright but by 4 pm it is just right. A variable aperture Hadley disk would be a big improvement.
The front aperture should be sized to fit the diameter of you bulls eye.
I like to use a 6 to 8 inch black bullseye at 100 yards/meters on a large white background with the heavy ring apertures that come with a Lyman 17A front sight. I can not see or use the thin ring apertures supplied for many BPCR rifles.
The entire basis of the apertures on a target range is a round bulleye with high contrast backing, aperture front, aperture rear. That is 3 circles that even fuzzy eyes can center.
You can shoot one inch groups with the right set up.