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O.K. got a S&W 15-22 and it has iron sights. Please correct me if my google fu is wrong;
1. Rear sight windage knob is 0.75 MOA per click
2. Front sight post is 1.875 MOA per detent
3. Rear elevation knob is 0.5 MOA per click

Thanks,

If those are the standard sights for the M&P15-22, they may not be the same adjustments as other iron sights. For instance, the A.R.M.S. #40L-P precision rear sight on my wife's carbine is .5 MOA clicks for windage, and the long-range aperture is much smaller than normal, and calibrated for use out to 500-600 yards (not that she'd ever actually shoot it at that distance). I'm not familiar with the adjustments on the standard front sight post.

I'm pretty sure most all GI rear sights are .5 MOA per click. This applies to Garands, M14's, and AR's. Not sure about the front site elevation changes on AR's.

Weg wrote:I'm pretty sure most all GI rear sights are .5 MOA per click. This applies to Garands, M14's, and AR's. Not sure about the front site elevation changes on AR's.

The Annoyed Man wrote:.....the A.R.M.S. #40L-P precision rear sight on my wife's carbine is .5 MOA clicks for windage....

A.R.M.S. iron sights are among the very best made.

A.R.M.S. #40L rear sight, .75 MOA:


A.R.M.S. #40L-SP (same plane system) rear sight, .75 MOA:


A.R.M.S. #40L-P (precision) rear sight, .5 MOA:


To me, it is significant that their #40L and #40L-SP both have .75 MOA windage adjustments, but their precision sight has .5 MOA adjustments. The #40L-P was originally "[d]esigned for U.S. Special Operations Forces and under contract with Crane Naval Surface Warfare Center. The P stands for precision." By the way, the MOA value changes according to the barrel length/sight radius. For instance, the Troy Industries Folding Rear Battle Sight specifies .5 MOA for the M16A4 rifle, but .33 MOA for the M4 carbine. Presumably, the same ratio of 1:.66 would obtain regardless of what the published MOA value is. So a sight which obtains .75 MOA on a rifle should give .495 MOA (effectively .5 MOA) on a carbine. . . . . .and the MP15-22 is a carbine. . . . .unless S&W specifies that .75 MOA is for a carbine length gun, and then ignore everything I've just written.

That ought to twist your noodle.

Weg wrote:I'm pretty sure most all GI rear sights are .5 MOA per click. This applies to Garands, M14's, and AR's. Not sure about the front site elevation changes on AR's.

I was off by 50%! LOL. Anyhow, I just looked it up, Garands and M14's were 1 MOA clicks, still not sure about GI AR's, but I bet they are to.