red dot and backup iron sights

artmcl

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I have posted a few times. but being new to the ar platform I have questions . I sighted my iron sights , then mounted the red dot the red is on a .8 in riser (a2 front sight) and sighted it in. When looking through the red dot, not the rear iron. the front sight is about 1/3 co witness If i try to look through rear iron
all I can see is the bottom of the red aperture I can not align the iron sights looking through the red dot; I do not know if this makes any sense am I doing something wrong

thanks for any help
Art
M&P 15 sport
 
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First question is what kind of red dot, and what kind of mount. I am going to guess a Bushnell TRS-25.
 
First question is what kind of red dot, and what kind of mount. I am going to guess a Bushnell TRS-25.
The is a truglo 2 color sight I know it not the best but I did not want to spend too much over $100
standard picatinni mount ( I know i cant spell)
 
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Is it a tube type red dot sight, or open sight? It sounds like the riser is too high. You need to lower the red dot so that your front and rear sights can be aligned in the lower portion of the field of view.

What does it look like if you just mount the red dot directly on the rail?
 
What's better- absolute cowitness or 1/3 cowitness??

I think 1/3 is clearly the better choice. You can still cowitness like you do with an absolute cowitness. I don't see how you can go wrong that way but I'm pretty sure I don't know everything. That's what my wife tells me and I do believe she "does" know everything. She acts like she does anyway, :)
 
Absolute blocks more of the optic's view than 1/3 does, so impedes target acquisition some unless your front sight is a folder, then it's a none issue. Outside of that, personal preference. It's not like the front sight is blocking the entire lower half of the glass.


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If you have flip up front and rear..... I like co-witness in the middle.. as I will only flip the sights up in an emergency.

If I have a fixed front sight I like....... 1/3 co-witness to keep the Front sight from interfering more than necessary as it's only going to be used if the red dot fails.
 
Good discussion (and video). I only have BUIS on my TS and that may end up being sufficient for my purposes and needs but this conversation is giving me food for thought down the road. Thanks gents. :cool:
 
The is a truglo 2 color sight I know it not the best but I did not want to spend too much over $100
standard picatinni mount ( I know i cant spell)

No sure what a truglo two color is or what riser you're using with it. But my guess is that it looks something like this? If so, you'll probably need a .5in riser for near absolute and .75 for lower 1/3. Specifics and a picture on your rifle would help. That said, you might consider returning it and get a red dot and riser combo that is designed to work with an AR platform. Something like a Bushnell TRS-25 and riser. These combos sell for well under $100. Visit Primary Arms for more red dot and riser combinations for ARs under $100. Much less problematic than wandering around lost in Walmart buying something to struggle with and end up tossing in the parts box.

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Absolute or lower 1/3..... there are many considerations.

Larger 30mm tube or smaller 20mm Micro?
Folding sights or fixed?
How much are irons going to be used?

I have folding sights, Aimpoint Micro and LaRue lower 1/3 riser. I don't use my irons much, but if I buy another riser it will be absolute. The reason is that with the rear sight large aperture the bottom of the scope housing is into the sight plane (blocking a portion of the aperture). Since I have folding sights, I'd prefer absolute for those seldom times I flip my irons into use. Now if I had fixed irons I'd for sure want lower 1/3 to reduce clutter from the tube. But if I used fixed irons and large aperture a great deal, which I never will, I'd want absolute. Make sense?
 
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Out of curiosity, do you guys leave the system affixed to the rail when you're cleaning or remove and reinstall afterward? Is it a pain to re-zero if removal is necessary?

At this point in life I much prefer simple and direct to complex and time consuming. (I realize that's a compromise in and of itself.)
 
My LaRue mount is QD. I usually take it off when working on the rifle. Return to zero isn't an issue. Decent mounting hardware usually doesn't suffer return to zero issues. Even with inexpensive mounting hardware return to zero isn't usually a problem, though cheap screws and QD mechanisms sometimes won't hold up to much on and off.
 
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Thanks, Phil, that's good to know. Who knows, maybe I'll have to put one on my birthday or holiday wish list so the missus won't have to bug me about what I want this year.

On the other hand, I continue to vacillate on whether, (for the kind of shooting I primarily intend with this rifle, 100 yards or less), they're more attractive because we can afford to add them than because we actually need them.

(As if "need" has ever been the limiting factor in the past. :rolleyes: :p)
 
I put a 1x red dot in the "NEED" column. It allows me to effortlessly focus down range on the target where my eyes should be, not struggling with old eyes on a fuzzy front sight post and ghosting rear sight aperture. 1x red dot makes everything easier, faster and better. It's a gift from the gods for aging eyes. Not only on a battle rifle, but my recreational handguns too. It turns a struggle into a pleasure to shoot.
 
I put a 1x red dot in the "NEED" column. It allows me to effortlessly focus down range on the target where my eyes should be, not struggling with old eyes on a fuzzy front sight post and ghosting rear sight aperture. 1x red dot makes everything easier, faster and better. It's a gift from the gods for aging eyes. Not only on a battle rifle, but my recreational handguns too. It turns a struggle into a pleasure to shoot.

Ditto.... and Ditto again.

One of the big reasons I've gone back to shooting more rifles over the past 3/4 years.... at 62....... red dots and scopes......
 
Thanks, gents. At 63 my eyes are still pretty good, (only need 1.25x reading glasses indoors, not outdoors), but the bit of astigmatism is a fuzzy pain in the butt at times.

I'll be sure to pick your brains either during a relevant sale or later in the year when gifts are in order.

I'd prefer to pick a good quality unit rather than scrimp and be sorry later. I think the "TS" deserves something along those lines.

I haven't done much, if any research but liked the reviews I read about the Aimpoint Pro. Then again, if equivalent quality and value is available at a lower price point, I'm definitely all ears.
 

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