Click the READ MORE below to read our article and watch the video on the Aimpoint Co-witness options for the Micro Series and an explanation of the two definitions used for co-witness on an optic.
Options for Co-witnessing Aimpoint Optics
by Jessie Indracusin
Background
First off, I am sorry for not even sitting down and doing a video explaining what co-witnessing is. There are two definitions on how to Co-witness an optic. So let’s start off by making sure everyone understands them. This becomes incredibly more confusing since different optic manufacturers will use the term that most benefits them when referring to Co-witness.
1) Definition #1: To Co-Witness an optic on a gun means that even if the electronic systems are down, your flip up iron sights can be used as a mechanical backup to an electronic failure. These sights will normally show up in the lower1/3 of your electronic dot system and remain visible in the event of a down optic. This definition is a definition that nearly all optic manufacturers are able to come up with some way of supporting.
2) Definition #2 (I like to refer to as sometimes the Aimpoint definition and the one I prefer): To Co-witness an optic on a gun means that the rear ring/wedge/etc. lines up it’s point of impact with the center of the red dot which lines up to the impact point on your front sight. This means you could draw a straight line from the rear sight, hit the dot and then hit the front sight.
Let me illustrate it with a few photos:
Eotech’s/most of the industry:
Notice how on the photo on the left, two different Eotech Models create two drastically different Co-witness lines. The Eotech 512 maintains a true co-witness to line up the iron sights, but the 516 sits up to high and allows you to only see the iron sights in the lower 1/3 of the window, the center of the ring not lined up with the iron sights. However, by basic definition, they are both co-witnessed because you can still see the iron sights in some form through the window in the event the electronic sights would not operate.
Aimpoint Co-Witness:
Now look at the photo on the left. All Aimpoint Optics with proper spacer kits line up correctly with a true Co-witness. The rear iron sight is looking directly through the center of the 3x Magnifier which is looking at the red dot that is in the center of the Aimpoint which is looking at the impact point on the front iron sight. Everything is completely co-witnessed with each other.
Aimpoint Co-witness options for the Micro T-1
I am going to skip the virtues of the Micro T-1 since I have covered that in another episode. What I want to tell you about and make sure you understand are the two primary mounting options. Each has a different price point and I want you to understand the pros and cons of each.
Aimpoint Spacer High Micro Series AR15/M4
This option is offered from Aimpoint and I sell them myself. The Spacer kit has an MSRP of $71.00. You can purchase it from me here at a cheaper price. I tend to keep them in stock for people who want to buy a Micro T-1 from me. They are assembled by unscrewing the four screws on the bottom of the Micro T-1 to disconnect the base and put this spacer in between the Micro T-1 and the old base and using the four longer screws included with the kit. This allows the Micro T-1 to sit up for a true Co-Witness with an AR15/M4 sights. This is a very basic spacer kit and does the job as needed. It is very cost effective compared to the other option I will be talking about, but is a rather fixed option since it requires a tool to take it on and off. Personally, I never remove optics from my guns since regardless of what a manufacturer says about returning to zero after it has been remounted, I still don’t like doing this. The only thing I want to mount and unmount is a magnifier for my gun.
LaRue LT660 Mount for Micro Series
This option is offered from LaRue and I sell it on my website myself. The MSRP is $133.00. You can purchase it from me here at a cheaper price and I tend
to always keep one around in stock at least. This is a popular after market option offered by LaRue who makes excellent mounts. That being said, they are very expensive. If you don’t care about price, this is an excellent mount. It allows you to mount and unmount the option with ease using a quick release throw type lever. The manufacturer claims a return to zero within a 1 MOA if I am not mistaken. If you are looking at an optic to move from multiple guns and you don’t care as much about having to re-sight an optic in for a different guns, this is the option for you. They are made of very high quality and I offer them to my customers who may not be as cost conscience.
Closing
I hope this helps clarify the term Co-witness and make sure when you are talking to a dealer, you have a clear understanding of what their definition of Co-witness is. The other reason I wanted to make this clear is towards the end of May 2010 I will be moving from an Eotech Reseller to an Eotech Distributor so I wanted to make sure I had an article and video to explain to my viewers the exact details of what I am describing here and not have to keep writing a very lengthy email over and over. We will be going through an Eotech price drop here once the new order comes through and I am cutting out my distributor from the middle.
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