View Full Version : AR-15 Aperature/Front Sight

Gregory Gauvin
December 5, 2009, 01:35 AM
Ok, so DPMS screwed my order up and I got sent a NM rear sight housing. The upper has a stock front sight post. Since I'll be upgrading to 1/4 clicks, I figured I might as well put in NM aperture and front sight post.

If I change my rear aperture from stock to .046", would it be wise to put in the .050" front sight post as well, or would it be OK to run with the standard .080" blade width?

I should I opt not to install my NM rear aperture, have you ever seen a rifle with stock front sight blade width and rear aperture size with 1/4 clicks or they tend to all be 1/2 clicks or 1 MOA clicks?

I figure, and tell me if I'm wrong, that since I already have a NM base, I might as well squeeze as much accuracy out of the sights by installing the NM front sight and aperture. It is my understanding that the smaller sights will render less room for error when sighting the target.

December 5, 2009, 08:03 PM
Personal preference.

As I recall from my Match shooting days with the M1, a NM front is sized to appear about the same width as the target.
This makes alignment errors easier to prevent.

December 5, 2009, 08:47 PM
Front sight post width is personal preference. One President's Hundred tab holder I know uses a front sight post wider than milspec front sight post.

As far as apeture sight size, and once again it is personal preference.

You have a very repeatable base, I'd put on whatever sight you have handy and enjoy it.


Gregory Gauvin
December 7, 2009, 03:06 PM
Are the stock, non-match AR-15 rear bases (the course threaded ones) not so repeatable? So I have heard the fine thread (NM bases) are repeatable, but the thicker courser threads are not. Is this true?

December 7, 2009, 06:05 PM
Of course 1/2 min clicks are repeatable. Lets look at it from a literal angle- the clicks are notches evenly arranged a 360 degree circle which has the center pivot (screw which the sight rides on) in the center. Now, I don't recall how many nothces there are, but for the sake of argument (looking at my clock on the wall) there are 12 notches for 1/2 minute and 24 notches for 1/4 minute. So, if you move X number of notches in any direction and then the same number back- then they are repeatable no matter how many notches you have. This counts for up and down too.