Using back-up sights?

If you have mounted a magnified optic then you must remove it before using MBUS. If you have a non magnified 1x optic then you can flip up your MBUS for use at any time provided your optic is mounted at the proper height for co-witness.

Below- 1x optic at lower 1/3 co-witness. MBUS can be used at any time.



chattanoogaphil-albums-pics-picture4100-dsc04392.jpg

I have a micro red-dot, and I can't seem to get the MBUS to co-witness, sadly. Maybe you have some tips? My microdot (looks like yours, really), is on a 1" riser to give my headset clearance and get my head off the stock. I think I need to put the MBUS on a riser, too, but I'm not sure what height things need to be at to work...

Thanks!
 
I have a micro red-dot, and I can't seem to get the MBUS to co-witness, sadly. Maybe you have some tips? My microdot (looks like yours, really), is on a 1" riser to give my headset clearance and get my head off the stock. I think I need to put the MBUS on a riser, too, but I'm not sure what height things need to be at to work...

Thanks!

What do you mean by you can't get them to co witness? When you flip up the sights what is obstructing your view?
 
I found the red dot a top the scope useless & ended up just taking it off.
I didn't try to tackle the red dot, other than to discover that it came incredibly far off from the factory. The red dot was literally 5 yards off paper at 25 yards. It was kind of funny to carefully line up the shot then see dust kick up three lanes over.
I didn't have the tiny screwdrivers to mess with adujsting it.
 
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Here's the issue. The front co-witnesses fine, but the rear doesn't because all I see is the bottom of the red dot when I look through the rear site.

No idea why the picture is upside down, sorry!
 

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I have a micro red-dot, and I can't seem to get the MBUS to co-witness, sadly. Maybe you have some tips? My microdot (looks like yours, really), is on a 1" riser to give my headset clearance and get my head off the stock. I think I need to put the MBUS on a riser, too, but I'm not sure what height things need to be at to work...

Thanks!

I'm guessing that the MicroDot has the emitter at the bottom of the optic so that's probably up into the rear sight aperture with a 1in riser. A .75in riser instead of the 1in should give you close to 'absolute' co-witness (in the middle of the MicroDot instead of the lower 1/3)

If your MicroDot has a removable base (4 screws underneath) then you can get a riser designed for it (the pic I posted) instead of a generic riser like you have now. LaRue LT660HK should lower it perfectly... but that's about the price of an entire new MicroDot and riser from Primary Arms.

The MicroDot in my the pic is Primary Arms Gen8. The emitter is off to the side instead of the bottom.

Take a look at what MicroDot you have to make sure, then it's easier to come up with all options that will work... but a $10 .75in riser should solve the issue you have now.

(MBUS will remain on the rail)
 
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Here's the issue. The front co-witnesses fine, but the rear doesn't because all I see is the bottom of the red dot when I look through the rear site.

No idea why the picture is upside down, sorry!

After standing on my head a bit to view the pic, just kidding, i copied it to something else and rotated it....

anyway, how does the front sight co-witness fine when its on the same line as the rear yet you say you can't co-witness with the rear?

this is your pic, I trimmed it down a bit and rotated it. I added the red line. The red line represents the center sight line through you red dot sight that you should be referencing, your riser is too high for any sort of suitable co-witness through the red dot. You can see from the pic that your not really co-witnessing with the front sight because the co-witness channel through your riser is blocked at the rear by the rear sight, so what your calling co-witness for the front really isn't because you can't align the front sight with the rear sight.

co-wit.png
 
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Haha, you guys. :D

Anyway, let me rephrase, because I really wasn't clear (too much orange juice or something).

I can see the front sight, but only because it's a half inch or so below the actual "projected" red dot. And yes, lol, I can see if it not using the rear MBUS of course!

Yes, I can't cowitness the rear and front MBUS sights, but I really love the height of the 1" riser. :(

It's a Konus 7247 - not sure if I can remove the base, but I haven't removed since it since it will require a re-zero which I've done 10 million times lately trying different riser heights!

http://www.midwayusa.com/viewproduct/?productnumber=318955

IDEALLY, I'd like the MBUS raised up some, too. My mathematics and ability to compute what I need is terrible. But say I like a roughly 1" riser for my red dot, what do I need to do to raise everything up and still have co-witness!?
 
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It's a Konus 7247 - not sure if I can remove the base, but I haven't removed since it since it will require a re-zero which I've done 10 million times lately trying different riser heights!

Konus Sight-Pro Atomic Red Dot Sight 1x 20mm 4 MOA Red and Green Dot with Integral Weaver-Style Mount and Rimfire Adapter Matte - MidwayUSA

IDEALLY, I'd like the MBUS raised up some, too. My mathematics and ability to compute what I need is terrible. But say I like a roughly 1" riser for my red dot, what do I need to do to raise everything up and still have co-witness!?

The base is not removable "Integral".

Options:
*Replace your 1in riser with a .75in.
*Remove your MBUS and forget about co-witness BUIS.
*Buy a new sight designed for an AR platform like the Primary Arms MicroDot Gen8 with riser.

Not an option:
Forget about putting risers under your MBUS... And even if you were to try (don't) I've not seen any riser less than .5 in. So all you would do (but don't) is lift your MBUS so high that you could not use your red dot or MBUS.
 
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Thanks for the reply. I guess I'm at a loss. I can't seem to find a .75" riser. Closest I can find is a UTG .8" riser.

If a sight is "designed" for an AR platform, how does that differ from my sight in terms of height? Also, say I were to go with the Primary Arms M4 sight, it seems like the lens is green? Why would I want green?

So many questions... :) Thanks. :)
 
Thank for for the link. I think the issue is that I want a 1" riser before my red dot... so... let's say I dump my existing red dot. What do I need to get that height with a Primary Arms dot? Which one?

Thanks again.
 
If a sight is "designed" for an AR platform, how does that differ from my sight in terms of height? Also, say I were to go with the Primary Arms M4 sight, it seems like the lens is green? Why would I want green?

So many questions... :) Thanks. :)

It would be the correct height for co-witness.

All these cheap illuminated sights have a green/grayish tint to them. In order to get clear glass you have to pay more... like an Aimpoint or EOTech. I haven't looked though an M4 but I doubt it's as dark green as that photo makes it appear. I have Sightmark, BSA, Primary Arms and Tasco red dots. All of them have generally the same tint to the glass.
 
Hmmm... see the one I'm using has clear glass. It's actually a very nice optic for the money, I thought. I may just remove the back-up sights, and just put them on my soon-to-be-bought AR15, and just use what I'm using on the 15-22.

So basically what you're saying is that the Primary Arms M4 would be the equivalent of a .75" height, so the M4 sitting on my 15-22 would cause me to have to put my head lower against the stock than my setup now?

Just trying to clarify here. Thanks again.
 
Your optic has the same green/gray tint. Put it up to a white wall and you'll see.

All optics designed to co-witness with AR sights are very close to the same height. Some are lower third co-witness and others are absolute.
 
My Konus sight is very close to what I see, when I point it at a white wall. It's very, very slightly warmer but certainly not green or grey. It's like a slight white balance adjustment to warmer (I'm a photographer :) ). If I had to describe it as a color vs a white wall in my house I'd say very slightly yellower/pinker. At the range I'd say there was no perceivable difference that I recall.

So if all optics designed to co-witness with AR sights are close to the same height as the AR sights (like the MBUS), then I just won't be able to co-witness with them with a riser. I absolutely need a riser because my headset gets in the way and it's just not comfortable to squish my head against the stock.

Thanks for all the advice, though. I'll definitely bear this all in mind when for when I get my AR15.
 
You might consider getting lower profile muffs rather than equipping the rifle to accommodate the muffs.
 
You might consider getting lower profile muffs rather than equipping the rifle to accommodate the muffs.

Lower-profile muffs don't have the noise attenuation that I need for a loud indoor range. I could always wear ear plugs, too, but then I can't hear when my wife/friends are talking to me. lol. Can't wait! :D
 
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