Astigmatism and aim

[thunderchicken]

First of all, you need to determine which eye is your dominant eye. If you don't know how to do this just ask, it's super easy.
Sure, every instructor I have ever been around will say ideally it's best to shoot with both eyes open. That's great in theory but just doesn't work for everyone in the real world.
If you are right handed and left eye dominant (or the opposite for a south paw), having both eyes open can cause cross firing because of the eye dominance taking over. My daughter has this problem and was finally able to find what works for her (she also has an astigmatism and had to wear a patch at home when she was little)
We mostly shoot shotguns but also pistols. For my daughter, the easiest fix was to simply close her left eye and force the non- dominant eye to take over. This has worked well for her.
She tried the scotch tape and dot sticker on her glasses to shoot with both eyes open, but she found it to be a distraction. She also pointed out that in the event she would be carrying and need her pistol she wouldn't have a sticker or piece of tape on her glasses. She made a good point. Some told her to learn to be left handed. That's just stupid as it is unnecessary and would take much longer to learn than adapting by closing an eye.
For shotgun shooting another option would be the sight blinder from Midwest Industries. It sticks to the rib with double sided tape and has helped a lot of people.
Many of the worlds best clay target shooters shoot with one eye open. If it works for you, don't let anyone tell you not to do it.

I so far have been blessed with good vision. As well as being right handed and right eye dominant. I shoot my pistols with both eyes open. But, I shoot clays with my left eye closed (to limit seeing movement in my peripheral vision). I know several shooters way better than I will likely ever be who do the same thing. Phil Kiner has a great video about dealing with eye issues for shooters. Might be worth a watch.

Oh and for iron sights on a rifle or pistol, another option is using some paint on the front sight post to make it more distinctly visible. Again this works well for my daughter and my dad who deals with some near sightedness issues. Lots of options out there, you just have to find what works for you

 

[russc2542]

I don't dispute what you say here, or russc up above, but both my brother and I can line up crosshairs on the target from a steady rest. We're not experts by any means, but it's not rocket surgery.

And I can see the possibility of parallax shift between shots if you don't line up the same way. But I shot 5 consistent holes at one POI, and he shot 5 consistent holes at a different POI, so no shot-to-shot parallax error.

One thing I can think of that may have changed was, I bet he had to focus the diopter for his eyeball. That might would do it?

.

I'm not meaning to diminish either of your shooting ability. I don't claim to be an expert but I do read a lot and have some experience that aligns with what I've read. Scopes are thought to be point and click, and they are to some extent, but they certainly get complicated the deeper you dig.

Focus of the scope doesn't change between eyeballs, that's between the subject and the optics. To simplify: using a magnifying glass to focus the sun on something, does the focal distance from the glass to the subject change depending on who's holding it?

Yes you can both line up the crosshairs, but parallax is when the crosshairs/POA look good but the optic path is no longer aligned with the POI. If you back up from the scope so the dark ring closes in you can see how well centered you are on it. If you shift to the side so the dark ring isn't concentric, you can adjust the scope to align POI/POA. then shift it so the ring is shifted to the other side, the POA/POI won't align. When you're centered in the eyebox and don't have the dark ring, it can be hard to tell how well centered you are.

Also, if one of you cants the rifle, it doesn't take much to throw the POI surprisingly far off. I put a level on my NRL22 gun and it's made a big difference. There was one match I missed a 5" plate by several inches (with a sub-moa setup) but looking back, the rifle was almost certainly canted because it was an awkward position.

 

[Lodge]

I recently had this happen: I sighted in a Eotech on a friend's AR. From 12 yards on a bench I placed 24 rounds on 8 different targets in the center 1/2" grid. I'm feeling pretty good about the accuracy of the optic. He comes over and every round he fired was low. Like 2" low. Of course I'm thinking "No Way"! We re-adjusted his optic pretty dramatically to account for the low shots and voila, he's hitting on target. Go Figure

 

[mousegun87]

So the age of needing glasses has reached me. A few years ago I was told I have astigmatism in my right eye. So far it is only for fine print but I remembered that close the one eye that is fine, would that cause me to shoot slightly left when using iron sights? I probably pull it left not knowing either.

I’m going to do some classes eventually on carrying and probably aim. Just wondering if eye issues could cause a slight issue also.

I have astigmatism since high school. It does not affect my aiming through iron sights when shooting. Red dot will look smeared or like a starburst if I don't have my glasses on. This is why I prefer the prism optics since the reticle is physically etched on the glass and it looks fine even without my glasses on.