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Old 10-25-2019, 03:26 PM
8milimeter 8milimeter is offline
Join Date: Oct 2009
Location: Frederick, MD
Posts: 951
Default Switching A2 to A4 ? about front site gas block

I see multiple A4 rifle with a standard front sight.
I was planning on getting a low profile gas block, but want to know if its a waste of $$. Does the standard sight cause issues with scopes.
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Old 10-25-2019, 04:24 PM
dw617 dw617 is offline
Join Date: Jul 2013
Location: MA
Posts: 529

Remember seeing this a lot when guys were transitioning, optic w/ A2 FSB. Now, a barrel or two later, everyone has the gas block. Consider that WOA's SR barrels do not come with the cuts for the A2 FSB anymore, unless you ask. When I did my conversions, I installed the gas block.
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Old 10-25-2019, 06:03 PM
HighpowerRifleBrony HighpowerRifleBrony is offline
Join Date: Nov 2015
Location: Texas
Posts: 165

I zero the irons and keep a DCH as backup. The FSB hasn't been a distraction except with an ACOG. Any shadow can be used for eye position check.
Distinguished Rifleman #2223
"Technique isn't something that can be taught. It's something you find on your own." - Bunta Fujiwara
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Old 10-26-2019, 08:25 AM
ceresco ceresco is offline
Join Date: Oct 2009
Posts: 7,676

Interesting that the standard A2 front sight does not seem to greatly impair the scope image. I have removed the sight pin for slight improvement, but simply hacksawing off the top is the simple solution. Good Shooting. ....
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Old 10-26-2019, 10:13 AM
champ0608 champ0608 is offline
Join Date: Sep 2010
Location: AZ
Posts: 151

It won't hinder you, and it looks more like a service rifle. Keep it on there.
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Old 10-27-2019, 03:48 AM
613jmm 613jmm is offline
Join Date: Dec 2009
Location: Jacksonville, NC
Posts: 1,277

At 3x magnification, it appears as a smudge towards the bottom of the scope view. 4x you can still see it as a blur depending on lighting. The only time I have seen mine is when the sun was behind me and it was reflecting off the FSB. Above 4x it is not visible.

If you do decide to remove it, I would not cut it personally. Since every FSB is drilled slightly differently, you basically have a custom installation on each rifle. If you want to return the rifle to stock configuration with the FSB, you would have a hard time realigning the new FSB to the current holes in the barrel from the original FSB, and previously drilled FSBs normally do not line up with your drilled barrel. When I decide to install a different gas block, I remove the FSB and keep it and the pins in a baggy which is marked as belonging to which rifle. If I want to go back to stock, I just pull them out of my spares box and put them back on with no problems.
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Old 10-27-2019, 08:39 PM
a6bn a6bn is offline
Join Date: Oct 2009
Location: Pennsylvania
Posts: 93

Richard, good to see you are getting into Service Rifle. I have multiple uppers with fixed FSB. I also have one where I cut the tower off. I like not having the FSB in my field of view as it can be distracting especially if the sun is glinting off of it. You can use sight black to cut the glare down.

If you have any questions about Service Rifle give me a call or email.

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Old 10-30-2019, 11:53 AM
Kilo-Sierra Kilo-Sierra is offline
Join Date: Feb 2010
Location: Atlanta
Posts: 555

A few of my SR's still have them. At 4x I don't even see it at all. At about 2x i can see it. At 1x it is very noticeable. Doesn't bother me. i'd leave it and get a good quality pinned removable carry handle and shoot irons every once in awhile.

I can shoot a one hole/one shot group at any distance....."If I do my part"

Keith Schachle

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