iron sight shooting

[jcaoloveshine]

how much of the target do iron sights usually cover at 100 yards? it seems almost impossible for 1-2MOA with irons at 100 because wouldnt the sights (mosin, mauser, etc) cover up far more than that?

[Dr. Peter Venkman]

how much of the target do iron sights usually cover at 100 yards? it seems almost impossible for 1-2MOA with irons at 100 because wouldnt the sights (mosin, mauser, etc) cover up far more than that?

Generally speaking yes, but it depends on the sight picture that your rifle can use effectively at 100 yards. Being forced to use a navy hold (the front post is where the bullet is going to go) will make it difficult to hit the X ring at larger distances since you're post is floating around looking for the exact 'middle' of a tiny dot (or what the circle appears like at long distances). Using a six o'clock hold (the front post being below the target, lets say on the bottom of a circle) is easier since you are looking for a definitive edge that your sights don't cover.

[maxicon]

The MOA of the front sight depends on the blade size and how far away your eye is.

You can measure it for yourself, using mm or inches, as long as you use the same units for everything:

Measure the width of the front post - call that W.
Measure the distance between your sighting eye and the front post - call that R.
Calculate the circumference of a circle with your eye at the center and the front post at the edge - 2 x 3.14 x R - call that C.
A circle is made up of 360 degrees x 60 minutes/degree = 21,600 minutes.

Divide W by C, multiply it times 21,600 - (R/C) x 21,600 - and that gives the MOA of the front sight.

So, if your front blade is 0.1", and is 20" away from your eye:

W = 0.1, R = 20
C = 2 x 3.14 x 20 = 125.6
(0.1/125.6) x 21,600 = 0.000796 x 21,600 = 17.19 MOA.


A 6 o'clock hold and a ton of practice is how you get MOA accuracy with a 17 MOA sight blade.

[AngelDecoys]

The MOA of the front sight depends on the blade size............

It will depend on the size of your post. I believe National Match front posts (M1A/Garand) are the same width as the black on a '200 yard' SR target at 100 yards.