TargetTalk

Need some advice regarding a problem with iron sights and vision. I shoot Outdoor prone and am a mediocre shot. Going back I few years I cleaned 50 and 100 yd targets routinely using metallic sights. The last couple of years I rarely clean even one bull.

Examples: At at recent 3200, my irons score was 1511 and the scope score was 1592. The conditions were nearly the same.

This morning I shot three A23 with irons and dropped 8 to 10 points per target. I put the scope on for the fourth target and scored 400-14X.

I have presbyopia. My distance vision is decent. Up close is not good. I have slight astigmatism and a hint of cataracts.

I used a scrip shooting lens at the 3200, corrected for a sharp front sight. Today I used a simple +1.0 diopter lens in my glasses.

My front aperture is clear with either of these lens but will fade if I hold too long. With the scrip lens the bull is faded. With the +1.0 it is dark with sharp edges.

With both lens I am firing shots that look and feel like they are centered but are nines, even eights on the A23. Sometimes I'll have what seems to be a large zero shift.

I have a +0.5 diopter lens for the front sight coming to see if that helps.

I like shooting with irons and really do not want to take the option offered to the 60 YOA folks of shooting the entire event with a scope. If I cannot get this situation fixed, I may be forced to go that route.

Any input on the root cause of this would be appreciated.

A few questions -

foresight size?
length of sightbase?
rear aperture size?

What is your prescription for reading glasses?

At my age, I still have near perfect distance vision but need +1.5 reading glasses - my shooting lens is +0.75 which is slightly stronger than the recommended +0.5 but allows me to get a sharp(ish) foresight without blurring out the aiming mark.
I found +1.0 blurred the target too much although the foresight was very crisp.

I don't think a small astigmatism would be a problem but the early stages of cataracts might be more of an issue.
It might be worth seeing if you can borrow a "known-good" rearsight/iris in case there's something amiss with yours.

FWIW I have a rear iris that I can't aim well with - I have no idea why as it seems to work perfectly and close examination with a magnifier shows nothing unexpected (like fluff, hairs or dead insects)...

K.

I'd add the following question to Kenney's list: height of rear aperture to bore vs centre of scope to bore?

If one is noticeably higher this could be affecting negatively and positively your ability to settle your head consistently and the relaxation of your neck and shoulder muscles.

Kenny, thanks for the reply.

Foresight = 3.8 mm (fixed interchangeable element style). Per Art Neergard's spreadsheet this gives a 3 MOA line of white around the bull. Visually the inside of the front aperture is more than 2X the outside diameter of the bull.

Eye to fore sight = 36.5 inch

Rear aperture size is variable depending on ambient light. I close it down then open just enough to get a bright image. I use a Merit adjustable. Yesterday I tried a clean, fixed rear aperture (about 1 mm) - no improvement.

I cannot locate my current eye Rx. Will keep looking.

Over the years I've made a collection of off the shelf and scrip lens for Junker and Knobloch frames. Last week I tried an old +0.75 lens and the foresight was completely out of focus. The +1.0 seems a good balance of fore sight and bull but I have a +1.25 on the way.

I was given an older Gehman rear (no Model number??). It has an adjustable aperture and an adjustable diopter correction. This unit may have some promise but it provides a very dark image so I have not worked with it much.

I get the same results with two rifles in different stock designs.

Sidebar issue: If you use a 0.5X magnifier in the fore sight, is it normal to use a corrective lens in the shooting glasses as well?

This situation is getting under my skin.

Tim

Good suggestion. Best I can measure with a vernier caliper:

Rear metallic sight center height above bore centerline = 1.425 inch

Scope center height above bore centerline = 1.625 inch

Iron sight line is about 0.2 lower than the scope. Is that enough to matter?

The rear sight, scope, rifle and stock are the same I've used for several years now. Of course I am not as flexible as I was back then

I hate to say it but there is one thing to remember;

GETTING OLD SUCKS!

I bet your iron scores are not the first thing to go South. The best thing you can concentrate on is shooting high x count 1600s with scope.

One person to solve the problem was Herb Holister in the 70's. He had to quit for a while when his eyes got bad, had the lenses replaced and came back as good as new. So maybe for you surgery could be the answer. But refer back to the above. Good luck.

I'm 65 and the effects of getting old do suck. But guys 20 years older than me shoot irons better than I shoot with a scope.

I don't get it. Seems to me if you can see the front sight and bull clearly it ought to work.

The 3.8 foresight does not seem inappropriate. 36in is what I'd expect for a 1913 with the rearsight back a little and moderate eye relief. The 1mm peep would be rather dark for me especially with a lens to correct my focal length. If the fixed aperture was about the same size as your iris setting, perhaps try opening the iris more.

As for sight height .2in can make a difference. Even if you adjust the cheekpiece between irons and scope, the lower position of the irons may be sub optimal.

As for the .5 foresight lens, yes I know shooters who use one with glasses. British NSRA rules allow this combination. The rear lens gives them distance focus, and the front makes the blurred target slightly larger.

Received a new +1.25 diopter correction lens for the shooting glasses and tried it out today. The fore sight ring is very clear and the target is black and sharp.....a gorgeous sight picture. The correction seems ideal but no joy on target. Still getting many wide nines that looked and felt to be center shots. Once again, pulled the irons off, installed the scope and shot cleans with a good (for me) X count.

Eighteen months ago we relocated to a semi-arid environment. Relative humidity ranges from 10% to 20%. I wonder if a dry eye would exacerbate the effect of astigmatism? This plus I doubt that I drink enough fluids. I have read that inadequate fluid intake can cause vision problems.

I'm running out of ideas. Next test will be with the new +1.25 shooting glass lens along with using saline eye drops and drinking a lot of water.

If this fails I'll be joining the visually disabled folks who compete only with a scope.

I would suggest opening up that front sight. I am 24 and shoot with a 3.8-4.0 in prone (light depending) with a 35 inch sight radius or so, and I am definitely not on the big side. Another thing you might think about is the distance between your eye and rear iris. Do you have plenty of space around the front sight? I think the front globe should take up about 1/3 of the area that you can see through your rear sight.
Good luck!
Matt

Matt

Thanks for the suggestions.

If I use a 4.0 mm front, the vertical edge of the four bull 50 yard target becomes visible and that causes me all sorts of grief - I want to hold away from it so it does not show in the sight picture.

I use old school equipment - Redfield International rear with a Merit iris type adjustable eyepiece and a Redfield International smallbore fore sight. The fore sight has an enlarged flange on the rear. Now I keep the Merit iris open far enough so there is a good line of white between the ID of the rear iris and the OD of the fore sight flange.

When this problem started my first thought was poor sight alignment. In bright conditions I often had the rear iris closed enough so there was no line of white around the fore sight. Lately I've kept the rear iris open far enough to confirm alignment at the expense of enhanced depth of field. With the new lens the fire sight is sharp even when the rear iris is way open.

My vision has slowly degraded for 25 years. Until now I have always been able to correct it well enough to stay in the game, even shooting with a front post sight in Service Rifle. I have a box full of obsolete Rx lenses and other gadgets. This current situation has me stumped, and frustrated because the sight picture looks great.

Will you be at the Firecracker 4800?

If my next test fails I'll email Lones and ask him to move me from Conventional to all scope category.

NMC -

I experienced a similar issue for sometime. I could clean targets routinely with a scope, but not with irons. I had made some changes over a period of time, but none seem to help. I was concerned that I had developed some bad 'habit' in my position somewhere, and was focusing on many different things to correct it. A very good friend of mine suggested that if it was happening with irons, but not with scope, then I had developed an aiming error, not a position error. He then used a key phrase which led me to my solution: your sights in prone should very nearly 'self center' themselves. The front globe should line itself up in the rear sight. Mine did not. In fact, I had to work at it constantly, and very many times, it wasn't perfect.

I fixed some of the problem by simply moving my rear sight forward on the receiver rail about half of an inch. It dimmed the sight picture slightly, but my front & rear sights self align now. the only thing I need to do is to align the front aperture around the bull.

Good luck in whatever you come up with!

-tc

This seems like one of those situations where a day with a SCATT system and some trial and error tweaking would probably be most enlightening.
I'd agree that being well hydrated can help prevent gross errors but I can't help but feel that there's something loose in the foresight or rearsight.

Does your rifle have an adjustable cheekpiece?

K.

tc

Good comments re: a natural alignment of eye and sights. That is on the list of things to try.

Thanks

Jim

Kenny

A strangely appropriate comment. Just a few minutes ago I went through the targets and notes from the last two weeks of testing. I'm using a vintage Redfield International Smallbore fore sight. The sight elements I use are modern clear Plexiglass.

A year ago I had a terrible time at a match. After one stage I found the entire fore sight was loose on it's base. When attaching the sight to it's base the screw can seem very tight without actually clamping the sight to the sight base. The screw may be binding in the sight as opposed to pinching the sight against the base. This happened to me again last week on one occasion.

The situation is more complicated. The foresight elements drop into the sight tube, then a sleeve slides into the tube to hold it in position, and a threaded cap holds the unit together. Twice in the last two weeks I've found the sight element loose. Seems the specific element I'm using may be a bit too large and it can be tilted rather than sitting square in the tube. The lock ring tightens but after some use the element seats itself flat, this leaves the lock ring not fully seated and the whole thing is rattling around.

I've been fixated on vision problems and ignored this situation. I have not located my journal since relocating but if I recall correctly my iron sight problems may coincide with my using this specific fore sight.

Don't laugh but both my rifles are Remington 40X. One is in an International style stock, the other is in a prone stock. Both stocks are laminated wood from Al Freeland. Neither has an adjustable cheek rest.

If this is the problem it is easy to resolve. Embarrassing to have overlooked the obvious, but I'll still be smiling if it turns out to be the root cause.

More testing next week....

I'll go back to an earlier point about sight height. Since your cheekpieces are non adjustable, do you have to raise the surface when shooting 'scope? As the 'scope is 5mm higher than your irons, you can't have the same pressure on the cheekpiece with both. It strikes me that if the height (and general position) of the cheekpiece is good with the scope, and the much higher scores suggest it's not bad, the cheekpiece will be too high for irons, so you would be pushing down very hard to aim which would disrupt the recoil.

Have you noticed a difference in the recoil pattern between scope and irons?

The minimal gap around the foresight tunnel won't help, just like a realy tight foresight can give an unreliable aim.

Since I have been using the Right Sight from Stallings my scores have increased. Call him at 770-599-0948. He may be your answer.

in addition to tims excellent suggestion to the difference in height between scope and irons, you are looking through a different part of your cornea and 'seeing' with a different part of your retina between scope an irons. That could be huge if there is damage to one of those. ( i have a scar on my cornea and if my head position is wrong i shoot bad)

Risers under irons wont cost much

redschietti wrote:Risers under irons wont cost much

I think he'd need a taller sight bases. The Redfield rearsight mounts onto a bracket at the side of the receiver rather than a dovetail at the top.

Can still be done though.

Tim S wrote:

redschietti wrote:Risers under irons wont cost much

I think he'd need a taller sight bases. The Redfield rearsight mounts onto a bracket at the side of the receiver rather than a dovetail at the top.

Can still be done though.

Tim

It begins to appear your diagnosis was correct. In the last few days I have learned that with both rifles, if I relax my neck completely my face "slides" down the stock and my line of sight is low and left of being center on the rear sight. I may have been using my head to aim the rifle without being aware of it.

These are both aftermarket target stocks. I installed one of the rifles in the factory original stock. It is a conventional "marksman" style stock. Relative to the other stocks the comb is narrow. I can position the cheekbone on the comb, relax the neck and have a line of sight in line with the rear sight.

I had not used this stock for several years and the weight reduction will require getting used to. But I am confidant the solution is at hand. I'll participate in a four day event this weekend. Two days will be with iron sights. That should tell the tale.

Many thanks Tim and to all the other folks who offered advice!