Mounting a scope on a rifle with A2 front sight post.

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[ARCHIVED THREAD] - Mounting a scope on a rifle with A2 front sight post.

Posted: 12/13/2016 1:14:38 AM EDT

I've seen some rifles with the A2 front sight post still attached with scopes on them. I've heard that the scope kind of looks around the sight but does this interfere with the sight picture at all? Is there a certain type of scope needed to see around the front sight or are they mounted high enough that it just sees over it?

Posted: 12/13/2016 1:21:37 AM EDT

[#1]

Without taking my rifle out of the safe I'd say anything over 2x will. The scope doesn't have to be completely over the FS

Posted: 12/13/2016 1:55:12 AM EDT

[#2]

Lower magnification, below 4x or so, you'll see a bit of ghosting depending on the optic. Shouldn't impact your ability to shoot at that magnification, but it could be a bit disappointing. Above that, it's not noticeable.

As an example, you might be disappointed with a 3x or 4x ACOG, but not a variable scope as once you crank it over 4x it's like the front post might as well not exist.

Posted: 12/13/2016 2:16:59 AM EDT

[#3]

I think I've owned just about every possibility, from 1X to 6.5X minimum magnification, with my rifles/carbines with the FSP and experienced zero issues.
Currently my 20" has a 4X ACOG and my 16" has a 3.5X ACOG. I don't even notice it at all.

Posted: 12/13/2016 2:23:52 AM EDT

[#4]

Quote History

Quoted:
I think I've owned just about every possibility, from 1X to 6.5X minimum magnification, with my rifles/carbines with the FSP and experienced zero issues.
Currently my 20" has a 4X ACOG and my 16" has a 3.5X ACOG. I don't even notice it at all.

View Quote

It ghosts in the lower half of the FOV with my 3x ACOG, 1990's 16" Colt AR15A3. Not a big deal though.

Posted: 12/13/2016 9:22:40 PM EDT

[#5]

I mounted a 1-4x24 Vortex Viper PST atop a government model Windham (20" barrel). Fully intending to remove the front sight (A2), I ordered a low profile gas block. The scope is attached to the rifle w/ an ADM Recon. With 1x I clearly see the upper 1/4 (approximately) of the front sight. Doesn't bother me in the least. I was pleasantly surprised. And of course, as I begin magnifying, it fades away. I just knew it was going to be a distraction which would be corrected only by removal. I was dead wrong.

Posted: 12/14/2016 10:17:49 AM EDT

[#6]

When I had my 14.5" setup in Mini RECCE format, I want to say the only time the FSB was even visible (and only partially, it never obstructed my view) was when my Leupold Mark AR was set to 1.5x.

Posted: 12/15/2016 2:31:51 AM EDT

[#7]

I borrowed a S&W from a friend to test drive. It had a scope and the front A2 sight cut off. It was a (literal) pain in the neck to get my eye into position for the scope, so you may want to figure out how high you want the scope first. It is possible that you may want scope mounts that put the sight line above the front sight entirely.

Posted: 12/17/2016 4:10:03 PM EDT

[#8]

Ignore the front sight base in your scope long enough and eventually the brain will filter it out completely. It will still be physically present but awareness of it will not.

Posted: 12/18/2016 8:21:44 AM EDT

[#9]

Like watching a ball game through a chain link fence. Your eyes focus in the field, not on the fence. Same with a scope. The FSP will not block the view from an optic above 1X.
At 1X the optic will still work, you will see a shadow of the FSP. Will not effect shooting. 2X and above, the FSP disappears.

Posted: 12/18/2016 8:31:46 AM EDT

[#10]

There was a day when this was the hot setup; because you could co witness irons at 1x, or if using a red dot, etc.

If you run 2x and higher, you will not see the sight, basically.

All the 1x scopes should not be an issue if you have the right reticle and it is setup properly.

I have three ARs with the fixed front sight base.

I have two without.

Burma Shave.

Posted: 12/18/2016 3:52:45 PM EDT

[#11]

So expanding the question a little deeper, at the lower levels, you can train the brain to ignore the sight. How does it work with a reticle that has markings on it? I am thinking about putting on a Redfield 2-7 with the accusight. Will the front sight mess that kind of optic up? Or will it work as if it was a regular 30/30 plex?

Posted: 12/19/2016 1:12:38 PM EDT

[#12]

It's not a train the brain thing -- it's literally impossible for the front sight to block the field of view at any appreciable magnification. You will probably see it at 2x (gone at 3x) but remove the front sight post and you're looking through clear area.

Posted: 12/19/2016 1:22:46 PM EDT

[#13]

Quote History

Quoted:
It's not a train the brain thing -- it's literally impossible for the front sight to block the field of view at any appreciable magnification. You will probably see it at 2x (gone at 3x) but remove the front sight post and you're looking through clear area.

View Quote

Would it throw off the optic at that 2x power?

Posted: 12/19/2016 2:31:51 PM EDT

[#14]

So would you even see the haze at 4x or higher? I might put something like that on it. I'm just curious about how much of a haze you'll see. I don't want to chop the front sight, just want to mount a scope for accuracy testing and plinking.

Posted: 12/20/2016 12:19:56 AM EDT

[#15]

If you have the sun behind you, sometimes you'll see a haze as the light reflects off the front sight.

Otherwise, don't sweat it. It works fine.

Posted: 12/20/2016 8:30:12 PM EDT

[#16]

You need to know the focus range of your scope. I have a Strike Eagle 1-6 that does not see the front sight at all. Most non red dot/ reflex sights will miss the front sight.

Posted: 12/21/2016 4:32:27 PM EDT

[#17]

My 4X ACOG shows a "shadow" but it does not interfere with utility.

Posted: 12/21/2016 9:05:12 PM EDT

[#18]

Posted: 12/22/2016 8:49:45 PM EDT

[#19]

I really like that reticle! What kind of setup is that? I had assumed the small dot with a large ring was an EoTech only thing.

Posted: 12/23/2016 9:28:19 AM EDT

[#20]

old leupold mark4 cqt

Posted: 12/24/2016 11:36:05 PM EDT

[#21]

Quote History

Quoted:
3x
http://i.imgur.com/VxIBxlH.jpg

1x

http://i.imgur.com/NzKzkFe.jpg

View Quote

The brain be trained. I had to look at these twice to recognize the FSB in the pics.
Nice Leopy 1-3x. I miss mine.

Posted: 12/25/2016 7:01:44 PM EDT

[#22]

So far I've liked it, I think an Acog would be better but so far I like it... Some day I want to sent it back to leupold for a reticle change and make it a CMR like on the HAMR's....

[ARCHIVED THREAD] - Mounting a scope on a rifle with A2 front sight post.

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