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Discussion Starter · #1 ·
I got an Aimpoint Micro T1 with the LaRue tall mount (1/3 cowitness) based on the advice of the guy at LaRue. I zeroed the T1 dead on at 50 yards.

Lately I have been taking some carbine classes that are more close range work rather than long range precision rifle stuff. With the 17S and T1 with tall mount it seemed that I had to hold off quite a bit at the closer ranges.

To reduce ammo cost at these classes, I picked up a 16S that I plan to use for most of the classes on the theory that the manual of arms will be the same and I can train on an identical weapon platform (aside from the recoil).

I have been working to sight in the iron sights and have read the various threads on this subject and now understand issues like sight over bore being 3.5 inches on the SCAR compared to 2.5 inches on the M4 a little better. I also now understand the theory behind the military sight in targets used at 25 yards with the expectation that your point of impact will be low but equivalent to a dead on impact at a longer distance. I plan to zero my iron sights on both rifles to the 25/300 BZO recommended in the manual.

First question. If the sight over bore on the SCAR is 3.5 inches with iron sights I assume that means that if I had the LaRue mount that provides absolute cowitness it would also have a 3.5 inch sight over bore for the T1. With my tall mount I am assuming that my sight over bore is larger and that this increases the amount of hold over I need to do at closer ranges. Is this correct?

Second question. Which cowitness (absolute versus 1/3) would be preferred for the SCAR? The LaRue guy said that the tall mount would be best because it would not require me to cram my head down as much when looking through the sight. However, in my training they are stressing the need for a repeatable cheek weld. I raise the comb on my stock to make it easier to do the cheek weld. Do you think that the difference between the two mount heights would be about the same as the difference of raising the comb?

Third question. Would what I am reading about the ballistic climb or drop at the different ranges with regard to the iron sights apply to the micro T1 in the same way? I am guessing that with the tall mount the 25 yard zero target drop amount will be larger than with the iron sights or with an absolute cowitness mount in the same way as it is larger for the SCAR than for the M4.

I have been going through the standard mental torment regarding optics. I seem to like the EoTech reticle better for close in work but the Aimpoint dot better for 100 yards. I had toyed with the idea of putting a magnified optic on the 17S and the Aimpoint on 16S, but my instructor says that I should have the same optic on both rifles from the point of view of burning in training repetitions. I tend to agree with this.

At this point, since I already have one Micro T1 and I feel that I like it better at longer distances I will probably get a second one for the 16S, but I am not sure if I made the right decision with the tall mount.

Thanks in advance for your advice.

Joe
 

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IMO you can't go wrong with the T-1 for most practical real world applications...once you get accustoming to shooting with this optic you should easily be able to reach past 100-200 yards. yes, you will lose some of the 17s range, but again for what it sounds like you want a T-1 will be a great choice.
 

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T-1 is great I have one on my light weight piston driven AR. I would have put another on my 16s but they are $$! So, I settled for an Aimpoint Pro on that one. BTW I use a DD tall mount on my AR so I can have a nice co witness.
 

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The guy you spoke to was thinking AR. The SCAR has an adjustable cheek piece, unlike the AR, and the difference between a SOCOM co-witness (lower 1/3), and an absolute co-witness isn't much, and has more to do with preferred sight picture than scramming your cheek down against the cheek rest. Choosing a taller base gives us a clearer field of view due to the front sight post being lower in our field of view.

i run, and prefer the ADM mounts over the LT mounts due to the design of the clamping action of the mounting levers, as well as allowing easy adjustment for undersized or worn 1913 rails.

Lastly, unless you're running NVD's, you don't need to spend the extra money on the T1. You can go to the H1 and have money left over for ammunition. PM me if you're wanting a 2MOA H1, and an ADM mount. I carry them, & can save you some $$$.

-SS
 

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I forgot to mention, we zero the dot on our MRDS units to co-witness with the irons so our dot to our over-bore doesn't change. The dot is still in the same plane as our iron sight....

-SS
 

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PM me if you're wanting a 2MOA H1, and an ADM mount. I carry them, & can save you some $$$.

-SS
The Aimpoint micro grows on me as time goes on.
Can you repost a few pics of your ADM mount/ Aimpoint (H-1, T-1) combos for left side chargers?

I"m on the edge of tossing the Larue HK (tools needed) mount.
The SCAR 17s and 16s transition usage is a few specs different, so the ADM wins.

So far, the ADM Atlas combo stole the show.
-looking to follow suit above the receiver too.

A speedy ADM system and multiple needy 1913 rails = happy customer.

Thank you.
 

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I forgot to mention, we zero the dot on our MRDS units to co-witness with the irons so our dot to our over-bore doesn't change. The dot is still in the same plane as our iron sight....

-SS
Elaborate this process further for the curious.
 

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I know an instructor (now with Magpul fwiw) who has been using SCARs for a while. He says he uses the Larue LT660HK mount with the T1. This puts it lower, and gives the same sight/bore offset as an AR. His reasoning for this is so he doesn't have to learn a different close range hold than what he has been using for the past 20+ years. I don't know if he has to change his cheekweld or not, but if so, I guess he finds that easier than having to remember a different hold up close.
 

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That makes no sense, and here's why...


We zero our iron sights at 25m. We mount our MRDS to the rail, choosing whichever mount that gives us our preferred sight picture through our MRDS - lower 1/3, or absolute co-witness.

We make our adjustments to our MRDS so the dot sits on top of our front sight post and we're done.

Our sighting picture doesn't change with respect to hold-over with the MRDS as the dot position doesn't change unless we make elevation (or windage) adjustments to either the MRDS or the irons.

-SS
 

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He says he uses the Larue LT660HK mount with the T1. This puts it lower, and gives the same sight/bore offset as an AR. His reasoning for this is so he doesn't have to learn a different close range hold than what he has been using for the past 20+ years. I don't know if he has to change his cheekweld or not, but if so, I guess he finds that easier than having to remember a different hold up close.
Can the ADM replace the Larue LT660HK at exactly the same height?
I am completely satisfied with the Larue LT660HK height.
I dislike the slower procedure switching between 16s/17s rifles and shotguns.
-The adjustment procedure along with Larue chewing on the 1913 picatinny to be specific.

Yes, understand it's a picky subject, but the height and mounting procedure is what is attracting my dollar.

I'm an ADM mount fan.
The ADM is so easy to use on differentiating specs of 1913 picatinny rails.
An atlas bipod is in the photos to show the ADM mount.
 

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For visual reference, see the image below. We zero the sights, and mount our MRDS, and then move the MRDS dot to sit on top of the front sight post.

The only difference between the absolute and lower 1/3, is the sight picture as the lower 1/3 unclutters the field of view...

-SS

Product Cameras & optics Camera accessory Camera Technology
 

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the lower 1/3 unclutters the field of view...
-SS
For an AR with open sights, yes, it makes perfect sense. Unfortunately in my experience using a lower 1/3 mount places the dot squarely overlapping the hooded front sight on the SCAR when deployed. Resulting in what I felt was a more cluttered and distracting field of view. I also noticed that when I shouldered the rifle naturally, the dot was always in the lower 1/3rd of the optic anyways, requiring me to use the cheek riser or adjust my stance to center it.

I've since switched to the Larue HK height mount that Steve Fisher uses as Barry mentioned. It's not absolute co-witness, but pretty darn close. Actually more of an upper 1/3 which gives me a clear view of the target through the hooded sight. It also centers the reticule in the window with a much more natural stance for me. You also get the added benefit of lowering the offset just a wee bit. Plus, I think it looks cooler (but that's just me!)

 

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...and it also brings the base into the sight picture.

The point to all of this is the factory sights are there as a back up. The QD mount allows us to quickly ditch the MRDS in the unlikely event that it, or the batteries take a **** at the inopportune moment - during a carbine course, or casual range session.

Given the fact that most all of us are shooting targets that do not shoot back at us, the discussion of MRDS position is mostly academic.

-SS
 

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Discussion Starter · #15 ·
Thanks for the prompt and detailed replies. I will re-read and digest once the sun goes down. I have to cut trees now while it is light out.

Sarge - I will research the ADM mount and consider for my purchase.
 

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Thanks for the prompt and detailed replies. I will re-read and digest once the sun goes down. I have to cut trees now while it is light out.

Sarge - I will research the ADM mount and consider for my purchase.
Enjoy the day Paul Bunyan!:th_sign0098:

-SS
 

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the most well know reason for the lower 1/3 co witness is as Sarge mentioned to enable dual deployment of both RDS and irons simultaneously. One must also consider your unique facial structure and shooting style.

Proper optic height is important to position your head in the correct position. Too low and you will be forced to bring your head slightly forward (chin to chest) to get a sight picture, too high and you will be having a chin weld on the stock vs a good cheek weld. You should find the height that allows a solid cheek weld with your head as upright as possible.

I will say that for the vast majority of shooters out there the difference of the lower 1/3 to absolute co-witness is not big enough to effect this but if your weird shaped melon falls on the ends of the spectrum this may be a consideration for choice of mount height
 
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