Hi all,
Just got my MP15-22 last week and today I got a reflex red/green dot scope. When I mount it, should i get a raiser and keep the front irons on? Or just take off both irons? Thanks in advance

Really depends on you and the red dot. If the red dot has cross hairs of other aiming in it that is visable with out being turned on then there is no real need for addition sights on the gun. If the red dot is just a clear lens when it is off then I would raise it and leave the factory sights on.
I have the Ncstar that is red/green but even when off the aiming focal point is still visable like a regular scope.

Are you wanting your red dot to co-witness with your BUIS?


I would at least get a flip up rear sight if you're going to keep the BUIS on IMO. It's really all up to you how you want it set-up.

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Sappers Lead The Way

This probably has more to do with personal preference than what "should" be done. Mounting without a riser may set your sight so low that it feels uncomfortable or unintuitive. You'll just have to try that out for yourself and see what you like. As for leaving the front sights on, some prefer to have a back up sighting option while others like an unobstructed view through the reflex sight. If you happen to have flip up sights on your rifle model, then this isn't really an issue as long as you can sight through the reflex while your irons are flipped up. So there's really no wrong way here, as I see it. Just what feels most comfortable to you.

Thanks for the input, I appreciate it

Unlike other long guns with a stock that drops below the bore, the AR stock is more in line with it. Due to that, sights and optics are raised above it so the shooter can get a proper cheek weld. You'll want to raise your optic. The .83 is about right.