Hope im not asking to many questions, but im reading alot about the different options on these guns. So..with a holographic optic like an eotech, or even just red dot say from primary arms or busnell, do most people Keep their front site up, or just keep their regular iron site and then co witness or line up the dot and the front iron site. Or should you just get rid of the front site all together , and get a backup flipdown site.

Whats the advantage when using a red dot with a front site. ?

Keeping the front sight , or attaching a folding front sight is the "safer" solution. If the holo sight goes down you can still effectively use your rifle.

I chose to retain the fixed A2 sight on my carbine, because it is a PITA to remove. I prefer to have the sight in the lower part of the field of view, so I opted for an EXPS2 from Eotech.

Its all about personal preference... i use to run mine with Daniel Defense fixed sights lower 1/3rd in my Aimpoint micro but now im running Troy flip-ups but still in the lower 1/3rd... you will have to try different setups to see what you like.

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SaveLivesKeepCiviliansArmed

Since my 15-22 is just a range toy, I took the MBUS off it and put them on my AR-15 as a backup for my Aimpoint. I just keep an extra battery handy for my 15-22's optic.

A fixed front in a co-witnessed setup has advantages and disadvantages.

advantages-
-It might be what you're use to, or stuck with if your AR15 has a fixed front sight/gas block
-The front sight is the one that will take more abuse
-It's one less thing you need to worry about if your optic fails (competition shooting)


disadvantages-
-Blocks half of the sight picture
-Ghosting with magnified optics (on lower settings)

I like my MBUS flip ups (in lower 1/3 when using the RDS) personally.

They are completely out of the sight picture for the majority of the time I spend using either the RDS or scope, seem to be less clunky/bulky and lighter than the stock fixed sights (and the rear flip up is a necessity to be able to use my scope or doubler on the red dot), and from a logical and anecdotal perspective seem significantly less likely to be damaged by use/abuse than fixed sights (or to a lesser extent other all metal BUIS).

This rifle is primarily just for range shooting and plinking/informal run and gun fun though. I do like flipping over to the iron sights for at least a mag or so on most outings just for the practice and change of pace.

Same here, folded down you have nothing to obscure the red dot but if needed (or as Sid mentioned you just feel like it) you can quickly flip them up.

I don't think you would lose much with fixed sights and lower 1/3rd co-witness but I haven't tried it.

I also use a lower 1/3 with MBUS, but you don't lose much with fixed sights. Many people use it with fixed front sights. I tried it recently and it works fine. You are more or less looking over them.

I still don't think there is much need for a full set of backup sights on a 15-22 because the shooting you'll be doing with it won't be life or death if the dot fails. That said a smaller aperture red dot like an H-1 and a front sight can be used very effectively for some shooting.

Have MBUS on my son's 15-22, because I had the rear sight on another rifle and did not like it. His are set for absolute co-witness with a Bushnell TRS-25. Will he ever need them, not likely, but they look cool and that is important to a 13 year old boy!

My rifle has a fixed front sight, with RDS co-witnessed for lower 1/3. One rifle has a folding rear sight, and the other has the LMT A2 sight.

You do not really use the red dot with the front sight at the same time. When using the red dot, focus on the target and place the dot where you want to hit. You will get to where you do not notice the sights.

What riser are you using with the TRS to get an absolute co-witness? I want to run that optic with the absolute co-witness and I'm thinking of using the UTG medium riser.

I believe it is the medium. I bought one of the UTG risers and it was the wrong height, but I had a rail in the parts bucket that did the trick. Going from memory, I think it is .83" riser.

Another consideration is that having a rear sight in perfect co-witness with your RDS is good for sharpening up the dot if your eyes aren't so good.

I have Keratoconus (w. corneal grafts & contact lenses) and some astigmatism, and I find that pin-holeing the dot through the rear aperture solves a lot of the problems with dot 'flaring'. I use an Eotech XPS2 with MBUS Gen2 front & rear.

.83 is correct. I found that info on a search last night and ordered the UTG .83 riser from Amazon for $7.20.