TargetTalk

Hi, I've recently joined a club and I'm undergoing training for prone target shooting. It's all going well except that I can only ever see a semi circle through the diopter rear sight. I changed head position and moved the sight to no avail, its a club rifle and no one else has problems so it's definately something wrong with me or what I'm doing.... any suggestions please ?


Regards
Aston108

A few questions or assumptions first.

I am guessing that you are using "diopter" interchangably with "aperature". Usually a diopter has some kind of magnification in it.

How is your vision overall? Has it been checked and do you wear glasses?

Due to the way the eye-sight system works the light and image coming through the aperature relies heavily on a very localized part of the cornea and lens (as opposed to just looking out the window where all light is incident on the entire surface of the eye's optical system.) If there is a problem with the localized area of the eye that is trying to focus the image coming throught the aperature it will manifest by a very poor sight picture image.

As you are just beginning I am not about to recommend you go drop a paycheck on specialized shooting glasses but try this with both glasses on and off. Also some people have reported decent luck with "poor mans" shooting glasses by taking a $10 pair of drug store reading glasses and bending them so they are looking straight through the lens while shooting.

If this rifle truely has a diopter (magnification in the rear sight element) then the correction is completely wrong for your eyes. (Like a far sighted person trying to wear a near sighted persons eyes.) Work the problem one step at a time, first make sure all the glass is out of the system and work up from there.

'Dude

its been sugested that I have a droopy eyelid.. could it be this ?

Anonymous wrote:its been sugested that I have a droopy eyelid.. could it be this ?

That could be an issue, especially if your head is too low down and not upright - in which case you'd be looking through the eyelid. Is someone coaching you and setting up your position - if so they should be able to tell if your head is in the right position.

Rob.

Anonymous wrote:its been sugested that I have a droopy eyelid.. could it be this ?

Yes.

The eyelid drooping will typically cause the rear aperture to appear semi circular, with the flat at the bottom.

If the stock has an adjustable cheek piece, fitting sight raising blocks and shifting the cheek piece higher will result in your head being tipped further to the rear, allowing clearance from the eyelid.

I've also seen someone use surgical tape on the eyelid :)

thats exactly what I see.. the flat at the bottom... time to get the tape out maybe

Anonymous wrote:thats exactly what I see.. the flat at the bottom... time to get the tape out maybe

As Bruce says, Raising Blocks should help - they'll get your head in a more upright position. A cheekpiece that you can adjust while in position is a wonderful thing.
Alternatively, your position might just be too low...

One wierd thing-anything coming down from the top be it eyelid or in my case mutant eyebrow shows up in the bottom of the sight picture.
Don't know why but just does.

Your eye flips the image upside down as part of the lense function.
Your brain erects it into an upright image.

Years ago I read of a study where glasses that inverted the image where given to test subjects.

In a few weeks there inverted images became normal. Upon removal of the odd glasses they then saw everything upside down.

http://www.colorbasics.com/Retina/

Michael

If you haven't let another shooter look through your reatr aperture, I suggest that you do. If he or she has no problem with it, you've got to see an eye doctor. MIke Barron