Ideal Front sight width

[marrandy]

Huzzah appleseeders.

I have a Midwest Industries front sight MCTAR-FFR.

My eye is approx. 17 inches from this front/fore sight.

After testing on various sized  black squares up to 10 MOA, it appears to me it is at least 14 MOA.  Thai Fighter tried it and thinks it is 15-16 MOA.

The big question...What is the best MOA for a front sight ?

I have a feeling 4 MOA would be good but would that be too thin ?

So I am after experienced   'iron sight'  shooters opinions.

Let the games begin   

[jmdavis]

Remember that the flip up sights were designed as backup sights. They are supposed to allow for fast engagement, not precision marksmanship.


The Whiteoak match upper has a front sight that measures out to ~10MOA (for me it is 10 MOA)

My Bushmaster HBAR (circa 1995) front sight is 7 MOA

My RR upper front sight is 7 MOA

My H&R 1955 M1 is 7 MOA

My 1903a3 is 6 MOA


I have an older match AR A2 sight that works out to be around 4 MOA

For my money I like the 6-8 MOA front sights it is useful to me for Ranging, big enough to see, and seems to do the job.

The 10 MOA makes it easy to put the "pumpkin on the post" though.

[marrandy]

OK - that's worth knowing.  I didn't know flip up sights were just back up sights.

See...I'm learning already  :-)

I've already emailed MI to see if they have any replacements.

[ItsanSKS]

During the same exercise, my 20" Armalite HBAR measured to 10 MOA. 


At 400, and 500 yards, this front sight seemed ridiculously large.

I had always been lead to believe that the front sight on the AR/m-16 pattern rifles were designed to correspond with the BSZ/PBR.  Is this not the case, or is the 'civilian' front sight different in width than the military front sight?  Or is this a M-16a1 (round front sight) / M-16a2 (square front sight) difference?


Regardless, I think I'll be going with the NM front sight replacement.  10 MOA seemed a bit huge for my taste.

[jmdavis]

OK - that's worth knowing.  I didn't know flip up sights were just back up sights.

See...I'm learning already  :-)

I've already emailed MI to see if they have any replacements.

It takes standard AR posts. But that might or might not help. If you have a 16" barrel, with a carbine gas tube, that would seem to be about right for the 17" radius that you are talking about. If your eye is at 17, the rear sight must be like 16 or less. Are you nose to charging handle? You might try the NM height front post that tech sights sells. These are around 4 MOA for me on the AR and might be 7 or so for your shorter radius.

[jmdavis]

During the same exercise, my 20" Armalite HBAR measured to 10 MOA. 


At 400, and 500 yards, this front sight seemed ridiculously large.

I had always been lead to believe that the front sight on the AR/m-16 pattern rifles were designed to correspond with the BSZ/PBR.  Is this not the case, or is the 'civilian' front sight different in width than the military front sight?  Or is this a M-16a1 (round front sight) / M-16a2 (square front sight) difference?


Regardless, I think I'll be going with the NM front sight replacement.  10 MOA seemed a bit huge for my taste.

Eric,

Be careful who you order the sight from, some NM sights are wide, some are narrow. The tech sights version was more narrow (at least the one that I bought for my ruger was).

Mike

[SPQR]

I use a DPMS NM on  RR 16" barrel and it works out to 5 moa.  I like it.  My vision has started going a bit but I can still make it out.  The real trick is that when I use standard posts and I focus on the post (I think I learned that somewheres) any target less than 6 moa completely disappears (I know the difference between "goes fuzzy" and "disappears").  With the 4 moa the issue is not as noticeable. 

I find the Tech Sight to be fairly exceptional as well.  It is a good height and tapers a bit. 

[marrandy]

MidWest replied to me.  They said:-

"We do not have thinner posts they are gi issue width."

I measured with a digital caliper.

The size I have is

0.06 65  also measured as  1/16"  and also measured as   1.73mm


Is that really 'GI'  issue ?

[mcnee229]

You can try some non traditional posts if you like: http://www.brownells.com/.aspx/sid=32950/pid=13802/Product/Front_Sight_Pack# or get a spare round one and chuck it up in the drill press, file down to whatever diameter or profile you like, and this one is supposedly .050" http://www.brownells.com/.aspx/pid=254/sku=062-111-100/Product/AR_15_M16_NATIONAL_MATCH_SIGHT_KIT

Scott

[ItsanSKS]

jmdavis-

Could you kindly provide a measurement of the width of your AR sight that appears to be 7 MOA?

[Aromatic]

Something worth keeping in mind is that some posts are not square.  They are unidirectional and should only be adjusted by one full rotation at a time.  If you happened to have one turned 90 deg, it could appear to be rather wide.  FWIW, I had a 0.052 post on a rifle and it looked ~ 4 MOA to me.  I thought it was a little thin for field shooting (although great for target shooting) and jumped to a 0.062 post.

[jmdavis]

The upper I need is not at the house right now. I should get it back this weekend to measure the sight width.

But here are a couple of more narrow sights.


DPMS Front Sight Post Square .050 Wide DCM-CMP AR-15 Matte

DPMS Front Sight Post National Match-Style .050 Round AR-15 Matte

Bushmaster Competition Front Sight Post .052" Width Square AR-15 A2 Matte

Check midway. All of these are about 15-20% narrower than the .665.

[Rocket Man]

During the same exercise, my 20" Armalite HBAR measured to 10 MOA. 

At 400, and 500 yards, this front sight seemed ridiculously large.

I had always been lead to believe that the front sight on the AR/m-16 pattern rifles were designed to correspond with the BSZ/PBR.  Is this not the case, or is the 'civilian' front sight different in width than the military front sight?  Or is this a M-16a1 (round front sight) / M-16a2 (square front sight) difference?

I believe this is correct, and not just for AR's.  My old M1917 Enfield has a nice, fat front post that worked out to exactly 8 MOA.

My AR-15 front post is 10 MOA, but that's on a carbine-length action, quality backup sights on a railed gas block. 

Believe it or not, after trying them I've grown to like the wider front posts.  Works better in failing light.  8 MOA is about right, in my opinion.  I just had to train my eye to keep the little black dot centered on top of the post.  Instead of "punkin' on a post" it's more like... an Apple.   

But fit whatever post works for you.

[marrandy]

I'll try a 0.034" square sight.  That should half my MOA down to around 8MOA.

I'll try to update when I install and test against sized Black squares.

[wcmartin1]

http://fulton-armory.com/frontsightpostnma2052blade.aspx

[Nickle]

The proper width front sight to use depends on what you're trying to do with it.



For a Battle Rifle, you want a front sight that will be torso width at your BSZ (Battle Sight Zero) range. For most rifles, that will be 7.5-8 MOA (and why the M1, M14 and 1917 Enfield sights are the exact width they are). Why that width is because you're using the front sight post as a range finder.



For a target rifle, you already KNOW the distance. So, proper width is based on your target. I recommend a 5 MOA width for the D targets we use, which are 5 MOA wide, if you check them (I'll qualify this with the word ABOUT 5 MOA, I may be off a touch, but not much).

Remember, we're shooting that AQT to a 400 yard standard, not 500. Your front sight will be about the same width as the D bull, and you can easily see if you are off a little horizontally when you call the shot.

FWIW, the 1903 Springfield was said to be the best target rifle fielded on the battlefield in WW1. They had target sights, not field sights. And, US troops knew how to shoot. At Belleau Wood, it's said the Germans thought they were up against a Battalion of Snipers, when they were up against Marines that were infantrymen.



The bottom line is that it's all a matter of what you're trying to do with the front sight (and the rifle) and what your personal preference is. That's why they make different width sights.

[marrandy]

OK - I received Two KNS precision 0.034" square posts.  They measure 0.93mm, 0.0365 in, 1/32 in.

I made up a sheet with 4, 6, 8, 10, 12 MOA, then a second one with 13,14,15,16 MOA.

My tests on the rifles were as follows:-

S&W M&P 15-22 Original sight post 16MOA, actual width 1.81mm, 0.0710 in,5/64 in.  Front sight to eye approx. 18".  With 0.034" post approx. 8MOA

Robarms XCR Midwest flip-up sights 15MOA, actual width 1.71mm, 0.06475 in, 1/16 in.  Front sight to eye approx. 18".  With 0.034" post approx. 8MOA

Alexender arms Grendel 6.5 AR A-frame front sight 15MOA, actual width 1.79mm, 0.0705 in, 1/16 in.  Front sight to eye approx. 18"

My wife's FN FS2000.  Front sight on rail 16 MOA, actual width 1.56mm, 0.0615 in, 1/16 in. Front sight to eye approx. 13"


I'm going to test the first Two actually shooting first.  The second at various distances.  If it works out well, I will buy another post.


That's all I have at the moment.


ADD:  To jmdavis - "Are you nose to charging handle?"   -   Yes, pretty much with the stock fully extended and  'turkey necking'.

[TaosGlock]

To determine how many MOA's your front sight is there is a formula.
Sight Radius Times 2 Pi divided by Front Sight Width. That number is then divided by 21600.
An example is my O3A3. It calculates to 6.1 MOA. So 6 MOA.
That is what most original/unsporterized 03A3 sights are. And when compared side by side to other battle rifle front sights,
a 6 MOA front sight looks very thin. It is also precise on the distant rams....at least for my eyes.
That covers a 1 1/2" black square at 25M.
Using the squares, you can more or less check/measure most front sights at 25M if your eyes are pretty good.

I have filed the sides of some of my front sights very carefully and can make them whatever suits my needs.

I have also filed the top of the front sight down on my M1A and M1 so when up at the 1000 yard target the rear sight is not so high,
is less woobly, thus more accurate...but that is another topic.