I currently have the OEG on my AR and I've had it for decades. Last class I took the instructors loved the old school sight but other shooters sort of poo-pooed it because it wasn't a Trij, Aimpoint or something else.

But when it came time to shoot, the OEG was very fast and I didn't feel outgunned, except when we went back to 100+ yards where the dot covered up the target.

Although I have no experience with sights like the Single Point OEG, the reason I’ve pointed out that this thread isn’t about sights that completely and continuously block vision with one eye is because those sights are fundamentally different from the ones discussed in the original post.

The obvious difference is that using the OEG sights doesn’t involve a switch from using a direct image of the reticle and target to using the combined superimposed image, and which can result in aiming errors if one’s eyes don’t function as (evidently) most people’s do. With the OEG type the combined image formed by the brain is always the same and if the sight is zeroed using that image the aiming conditions are always the same and don’t vary depending upon whether the front of the sight is occluded.

Or at least that’s the way it seems to me with no personal experience with something like the Single Point. But if I’m wrong and the phoria defect would also affect using the traditional OEG sight, then the fact that people can use such sights effectively just means that not everyone has the phoria defect. Something that we already knew.

But as somewhat of a drift (it’s my thread) and comment about the OEG type sights, has anyone ever considered how using that type would be affected if in a serious situation one eye were injured and the binocular vision thing would no longer be usable? I have good distant vision in both eyes and if my dominant eye were injured I could still sight effectively by switching shoulders to using the other.
Such sights were far superior to irons for certain applications back in 1970, such as during the Sơn Tây prison camp raid, but today? Usually usable, certainly; the best?

quote:

Originally posted by sigfreund:
Although I have no experience with sights like the Single Point OEG, the reason I’ve pointed out that this thread isn’t about sights that completely and continuously block vision with one eye is because those sights are fundamentally different from the ones discussed in the original post.

The obvious difference is that using the OEG sights doesn’t involve a switch from using a direct image of the reticle and target to using the combined superimposed image, and which can result in aiming errors if one’s eyes don’t function as (evidently) most people’s do. With the OEG type the combined image formed by the brain is always the same and if the sight is zeroed using that image the aiming conditions are always the same and don’t vary depending upon whether the front of the sight is occluded.

Or at least that’s the way it seems to me with no personal experience with something like the Single Point. But if I’m wrong and the phoria defect would also affect using the traditional OEG sight, then the fact that people can use such sights effectively just means that not everyone has the phoria defect. Something that we already knew.

But as somewhat of a drift (it’s my thread) and comment about the OEG type sights, has anyone ever considered how using that type would be affected if in a serious situation one eye were injured and the binocular vision thing would no longer be usable? I have good distant vision in both eyes and if my dominant eye were injured I could still sight effectively by switching shoulders to using the other.
Such sights were far superior to irons for certain applications back in 1970, such as during the Sơn Tây prison camp raid, but today? Usually usable, certainly; the best?

My sight is the Armson OEG and if I lose vision in one eye, there's no workaround that lets me continue to use the OEG. All I can do is look at the irons.

Today I had a chance to conduct an occluded sight test with a SIG ROMEO2 sight mounted on a 9mm P320. The test consisted of firing 10-shot groups from a firm bench rest. Ammunition was CCI 115 grain FMJ Blazer aluminum.

The first photo shows the results from 10 yards. The lower set was fired with the sight used normally, and the upper set with the sight occluded and aiming by using the combined visual image of the reticle with my right eye and the target with my nondominant left.





The second photo shows the results from 15 yards. The upper set was fired with the sight used normally, and the lower set with the sight occluded and aiming by using the combined visual image of the reticle and the target.





Using the majority of hits for each set and rough measurements, changing from aiming normally and seeing the target through the sight to covering the front window of the sight and aiming by using the combined mental image of reticle and target caused a significant point of impact shift at both 10 and 15 yards. The total shift at 10 yards was about 2.75 inches and at 15 yards about 3 inches. None of the sets was particularly small and all showed noticeable horizontal stringing which now I believe may have been due to parallax issues (more about that below). I do believe the results were clear enough for my point here.

As mentioned in earlier posts, the point of impact shifts from using the sight normally to its being occluded may be due to the phoria vision defect*. According to online sources, one type of phoria or another may affect from about 20 to nearly 40 percent of the population. It’s therefore important for anyone who plans to use or teaches the use of the occluded sight combined visual images technique to be aware of what effect that can have on firearms accuracy. The, “All you have to do is shoot with both eyes open,” advice may not work for everyone, especially if we are expecting to deliver extremely accurate shots because we have an optical sight. Anyone who might anticipate using the occluded sight technique should perform their own similar experiments.

Parallax. It’s commonly believed that illuminated dot reticle sights of the type I used for the test don’t exhibit any parallax shift. That is, users are told that as long as the reticle is visible in the sighting window, it doesn’t matter where it appears in the field of view, and shot impacts will all be the same if the reticle image is the same place on the target.
That’s not true. At least not with all sights, and perhaps with none of the type.

The way to check for parallax shift is to firmly fix the sight in position with the reticle likewise fixed pointing at a distant target spot, and then move one’s head around so that the reticle image moves within the sight field of view. If when the reticle changes position within the sight window it also changes position with respect to the distant target, then the sight exhibits parallax shift. It typically isn’t very much, but in my tests it’s readily visible. When I used that test method with the ROMEO2 sight without shooting, I saw the reticle apparently shift position with respect to the target at a couple of hundred yards.

I believe the reason the groups in the above targets showed horizontal stringing was because I was not as careful as I could have been to ensure that the reticle was centered in the sighting window for each shot, either when sighting normally, but especially when using the combined visual image when the view of the target through the sight was blocked. That’s particularly apparent in the 10 yard occluded set.

To reiterate my position on all this, it’s not to encourage or discourage the use of optical sights on handguns, but rather to point out facts that may be important to some users.

* Nope, that wasn't it: See my 15Feb24 post about me and phoria.

This message has been edited. Last edited by: sigfreund,

Interesting that you saw a bit of drift to the the right, which is consistent with my experience as well. I will say, though, that the shift isn't significant enough inside of 15 yards for either of us to be a significant factor for practical, center-mass type hits on a human torso. If the target presented is smaller, it could be an issue.

Yes, the shift isn’t that great and I expected that to be pointed out.

But one of the first things that’s always mentioned about the advantages optical sights on handguns confer is the ability of the shooter to deliver more accurate shots than with irons. If an LEO, for example, were faced with making a hostage rescue head shot from a distance of 10 yards without the benefit of a firm support rest, and the front sight window were obscured—admittedly, both very unlikely events—then an almost 3-inch POI shift could matter. I don’t know how well I’d do in a life or death situation like that, but under normal nonstressful conditions using irons I can avoid hitting that far from where I want my bullets to go.

Based on my earlier experiments with a rifle sight, the POI shift that is apparently due to phoria* becomes greater at longer distances, and therefore becomes more important at longer distances.

In addition, if my belief is correct that parallax affects POI more when using the two-eye occluded sight method, then that’s something else that should be understood for anyone who might anticipate using such sights for serious purposes. Note that I believe that’s the reason why some of my occluded sight shots at only 10 yards were shifted nearly 4 inches from those fired normally. The groups tightened up significantly only after I tried to ensure that the reticle was positioned in the same place within the sight window for every shot—something we’re currently confidently told isn’t necessary for accurate results with this type of sight.

Right now I suspect that most users of the sights believe what we’ve long been told that parallax isn’t something we need worry about with the sights.

At present the questions about occluded sight shooting aren’t important enough to me to spend more effort exploring the matter, but it would be interesting to know when/if anyone conducts similar experiments and their results. My experiences thus far have obviously been very limited, but the results I’ve seen have been enough for me to question whether the conventional wisdom about nonmagnifying “red dot” sights is as wise as most of their users believe.

And to wrap up this post, I’ll readily acknowledge what probably most people who’ve gotten this far have noted that it’s very unlikely a situation would occur in which only the front window of a handgun optical sight would be obscured while allowing the illuminated reticle to still be visible at the back. In fact of course it’s far more likely that rain, snow, dirt, clothing lint, or even a spilled milkshake will cover the rear window and especially the very vulnerable open emitters. In that case we’re back to the incident I described with the shooter who allowed snow to cover the rear lens of his rifle sight, and none of this discussion about two-eye shooting or parallax would be relevant.

* Nope, that wasn't it: See my 15Feb24 post about me and phoria.

This message has been edited. Last edited by: sigfreund,

Like anything, there are advantages and disadvantages. Is it possible that the optic on a duty handgun could become occluded, or the emitter blocked during a critical event? Absolutely. It's also possible that I might be in a situation where I have to take a very difficult shot and my clear and perfectly functional red dot provides a distinct advantage. Overall, I think the latter is probably more likely.

What we're doing here is game-planning a contingency for a worst-case scenario, and IMO there's absolutely value in doing that...but it's also necessary to remember that's only one small portion of the greater risk/reward calculation.

I've been carrying a red dot on duty for almost two years now. So far in working the road and wearing normal duty gear, I have yet to have to deal with a completely occluded optic. I've had one premature battery failure (factory battery that I should have replaced out of the box...live and learn, I now replace every 6 months) and a zero shift that I noticed immediately due to my morning ritual of checking the dot against the irons. Twice my Romeo1 has failed to wake up from a MOTAC induced overnight sleep...pressing a button resolved that (this has only ever happened when taking it out of the safe in the morning, never when coming out of the holster). I've also learned that it sucks to shoot into the sun as it can produce "ghost" dots on the glass and you have to spend a lot more time making sure you're referencing the correct dot.

Truth be told, most of the issues I've experienced so far would be better addressed by training on forced sudden and unexpected transitions to the backup irons than working on occluded optic. The occluded optic drills do help force target-focus, though, which I appreciate.

quote:

Originally posted by 92fstech:
Truth be told, most of the issues I've experienced so far would be better addressed by training on forced sudden and unexpected transitions to the backup irons than working on occluded optic.

Thanks for that. The opinions of experienced users are what really matter.

I'm now coming up with some nasty ideas for what to do at our next range day !

During a post-cataract surgery check today I asked the optometrist about phoria. After I explained the reason for my interest she again conducted a test that I’d undergone in all my previous visits, but didn’t know what it was for. She told me that my vision in that regard was normal based on the test results.

The test obviously indicates that the results I obtained in my experiments with shooting while the optical sight was occluded were not due to that particular vision defect.

Anyone else conduct their own experiments?

For our department training course to use a MRDS we use painters tape to Occlude the red dot. Both tape on the front of the glass and the rear of the glass. Also spray water on it as well. We also train with the dot in the “corners” of the glass as well like we do w/ the red dots on rifles. Guys are really suprised on how well they are getting good hits w/ tape over the glass.

quote:

Originally posted by 357fuzz:
Both tape on the front of the glass and the rear of the glass. Also spray water on it as well.

Good suggestions; thanks for the ideas.

Sigfreund. I’m not a big fan of the enclosed emitters but, the one advantage of them is with the water spray test. When fired the recoil really shakes the water off of them. Fore and aft. The open emitters will let the water puddle up especially in the SRO’s. But a shot or two or a quick shake it is pretty much gone. It also shows that the red dot still works and you will be on target.

I take a spray bottle and give the red dot a couple squirts when the guys are holstered on the line. I also then give a couple squirts(carefully) when the guys are drawn pointed down range from the sides on the front and back of the MDRS for an additional drill.

Tape on the front of the glass easy to get good hits. On the back of the glass it is different. Putting the dot in the corners. Is to simulate not getting a real good dot on target in your ideal place but to demonstrate how little you will be off. Some people think if the dot is not dead balls on the target the evil dot will send the bullet so far off course it will take down the Goodyear Blimp flying over Pasedena CA while you are firing MRDS equipped pistol from Waco TX. People have been doing that drill for years w/ red dots on rifles at 50 and 100 yards and a properly zeroed dot is not far off. In my experience maybe an inch. On a handgun w/i 25 yards the shift is even smaller.

Sigfreund, I was listening to Lee Weem's podcast today (actually a guest episode with Erick Gelhaus and Mike Ochsner) and there was some interesting information about eye dominance and its application to aiming with a red dot optic. It was relevant to the discussion in this thread, and I thought you might find it useful, as I did. The specifically applicable portion starts about 30-35 minutes in to the episode.

https://podcasts.apple.com/us/...1538?i=1000645857726

quote:

Originally posted by 92fstech:
Sigfreund, I was listening to Lee Weem's podcast today ....

Thanks for that. I don’t do well with podcasts in general for a few reasons and this one was no exception, but I did listen to the segment starting where you recommended. That and what followed piqued my interest enough to order the Red Dot Mastery book by Ochsner. I’m looking forward to reading it and better understanding some of the things that were discussed.

https://www.amazon.com/gp/prod...00_s00?ie=UTF8&psc=1

And I see that the author has another book that looks interesting as well. I’ll see what I think of this one first, but I was impressed with his delivery in the podcast.

Again, thanks for the link and recommendation.

No problem. I haven't tested any of the stuff they discussed for myself or anything like that, but I thought it was interesting and immediately thought of this thread. Please let me know how the book is...if it's good I might be interested in picking up a copy for myself.