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Co-witness your optic? Why?

2307 Views 31 Replies 22 Participants Last post by tarheel7734, 11 mo ago

CybrSlydr

Discussion Starter · May 26, 2022

My brother has a P320 XCompact with the RDS. Nice gun, shoots well - but why do you co-witness the irons with the optic?

To me, one of the biggest plusses of an RDS is the open view. You don't have the slide at the bottom getting in the way of aiming. To me, it makes it easier to put the dot on target if it's not co-witnessing.

Also, if you co-witness, why bother with the RDS if you're still aiming with the same irons?

Is it in case of optic failure or battery dies at the worst time so your training is still good? Is it so the RDS aim/muscle memory is easier to transition if you're still aiming at the same space/point?

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DMCutter

· #2 · May 26, 2022

You don't. Find Sage Dynamics' video on why you don't slave a red dot to irons.

Reactions: 5

Hammer

· #3 · May 26, 2022

I think there is widespread confusion about what "co-witnessing" actually is, and I bet I'll get some disagreement on what I'm about to say, but here goes:

In my opinion, "co-witnessing" means using your iron sights as a reference for your red dot, and essentially "slaving" your red dot to the irons. There are multiple reasons why I would not recommend doing this on a carry pistol, and I don't want to re-hash all that in this post. But suffice to say I fully agree with you that lining up iron sights in order to determine whether your red dot is on target or not is ridiculous, and totally unecessary.

Merely having backup iron sights that are visible through your optic window, but which are not "zeroed" off of each other, and essentially operate as two separate, independent sighting systems, is not "co-witnessing" - it's merely having BUIS. While pistol red dots have come a long way in the last 5 years, and are infinitely more reliable than they used to be, I still believe in having BUIS if it's going to be a defensive pistol. I just don't describe them as being "co-witnessed."

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CybrSlydr

Discussion Starter · #4 · May 26, 2022

Well, my understanding of "co-witness" is that when the iron sights are properly aligned as if you were shooting, the red dot is where the dot on the front sight post is.

Am I misunderstanding the term or is that pretty much correct?

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Hammer

· #5 · May 26, 2022

CybrSlydr said:
Well, my understanding of "co-witness" is that when the iron sights are properly aligned as if you were shooting, the red dot is where the dot on the front sight post is.

Am I misunderstanding the term or is that pretty much correct?

That is what I would call "co-witnessing" as well, yes.

But I've also heard people state that merely having visible iron sights at all in your optic window amounts to "co-witnessing."

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Jbt1892

· #6 · May 27, 2022

Co-witnessing is a legacy habit, a lot of people don't completely "trust" the red dot and want some sort of an accuracy confirmation. Happens with any technology. A few years back, some of my family members and friends stubbornly used paper maps over a GPS.

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Hammer

· #7 · May 27, 2022

Jbt1892 said:
...A few years back, some of my family members and friends stubbornly used paper maps over a GPS.

Wait - are we related?!?

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jthrelf

· #8 · May 27, 2022

Cowitness - no. Backup sights - yes.

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SimonRL

· #9 · May 27, 2022

On a lot of pistols it’s actually difficult to cowitnees the sights and often times it’s more of a 1/3rd witness. I have red dots on almost all of my pistols but I don’t go out of my way to make sure they cowitness because I’m really only interested in the red dot. I’m fact, on a couple of my guns I haven’t bothered to put suppressor height sights on. If I go into a defensive situation and my red dot is not available for whatever reason, I’m going to point shoot. I train regularly with my red dot and it is my go to. I get concerned that in a defensive situation people new to the red dot will spend that extra second or two to line their red dot up with their front sight and they will pay the price for it. If you want to use your iron sights as a back up, fine, but if you’re going to run a red dot get used to working it alone, knowing that where the dot is sitting is where the bullet is going.

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Navy87guy

· #10 · May 27, 2022

I only have red dots on some of my rifles. I zero the red dot from a rest. I zero the iron sights from a rest. Most often, the two zeros match up, with the red dot right on the tip of the front sight.

I have light/laser combos on my two HD guns. In those cases the lasers and the iron sights don’t align…but using either will out the round on target.

I’m comfortable….

weatom

· #11 · May 27, 2022

Jbt1892 said:
A few years back, some of my family members and friends stubbornly used paper maps over a GPS.

LOL!!! Reminds me my friend insists on using Mapblast and gets lost almost every
single time. I say "just use Google maps" for crying out loud. Nope, only uses
Mapblast

Firearms Collector

· #12 · May 27, 2022

Jbt1892 said:
Co-witnessing is a legacy habit, a lot of people don't completely "trust" the red dot and want some sort of an accuracy confirmation. Happens with any technology. A few years back, some of my family members and friends stubbornly used paper maps over a GPS.

I still Use Them combined with Mapquest. I have them for every State plus the Canadian Provinces..

alexc051

· #13 · May 27, 2022

cowitness was meant for rifle optics with backup irons. absolute or lower 1/3.

you don't do it for handguns

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SuzukiGS

· #14 · May 27, 2022

My sights co witnessed with my irons by themselves. At the distance I have my red dot setup I adjusted the Red dot at the range until it was hitting where I needed and it just so happened to be on the front post dot. Which is good for me since it’s my first RDS and I’m used to punching out and aligning the irons. I did have to change my draw slightly to pick up the red dot sooner but overall it was a very easy transition.

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Flash LB

· #15 · May 27, 2022

Hammer said:
That is what I would call "co-witnessing" as well, yes.

But I've also heard people state that merely having visible iron sights at all in your optic window amounts to "co-witnessing."

Nope. Just having them visible isn't co-witnessing.

I set up the dot, then co-witness the iron sights to the dot. The whole idea is if the dot malfunctions, the iron sights will be sighted in and you can use those.

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Nickp

· #16 · May 27, 2022

When I got consistent with my irons I then aligned my RDS. When I finished aligning my red dot...SURPRISE !...when I use either one the target moves right in front of the bullet for both...MAGIC...!

I have no idea what "co-witness" is but whether I use the irons or RDS, the bullet goes where I aim. It just can't do anything else...

My suggestion would be to align your irons until you're happy...then align your RDS until you're happy. At that moment in time you will be twice happy...

...or maybe it's called "co-happiness"...

Reactions: 3

LimaCharlie

· #17 · May 27, 2022

3

The suppressor height sights on my FN FNX-45 Tactical automatically aligned with the green dot on the Holosun.

Trigger Air gun Wood Gun barrel Gun accessory

Wood Hardwood Handgun holster Athletic shoe Strap

Watch Wood Household hardware Handgun holster Rectangle

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Hammer

· #18 · May 28, 2022

It's entirely possible that in the end, sighting in your RDS and your irons independently, that they may end up aligned. It's also possible that they won't. Possible - but also coincidental.

Reactions: 1

Nickp

· #19 · May 28, 2022

I would suggest that there is a fundamental thing going on...the DRIVER is the barrel. Ultimately, the barrel determines where the bullet goes. If irons are aligned so that where the barrel puts the bullet is where you aim (and do whatever it takes to make that happen) the irons are aligned to where the barrel puts the bullet. If you do the same with the RDS the alignment of the RDS is again (an absolute must) driven by the same barrel. There is no way (if each is aligned to POA/POI) that using either one will not hit your target at exactly the same place (give or take what the operator introduces).

YMMV...

Reactions: 1

ProofMark

· #20 · May 28, 2022

Jbt1892 said:
Co-witnessing is a legacy habit, a lot of people don't completely "trust" the red dot and want some sort of an accuracy confirmation. Happens with any technology. A few years back, some of my family members and friends stubbornly used paper maps over a GPS.

I have BUIS with my reflex sights, I carry paper maps in my car and I wear suspenders with my belts.

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