Has anyone ever installed a A2 FSB on a new barell?

slugworth

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It looks like it would have to be drilled and reemed with pins ect.... Not to mention be straight too.

I know they make the clamp type but they seem expensive!

Might be more work than I want to try myself.
 
I havent done it myself, subbed it out to Saxonville Armory and he did a great job. I thought about doing it and you would need a proper sized drill bit, taper reamer and taper pins.
 
You are probably better off going with a clamp-on flip up front sight gas block. YHM makes a good one, as well as some others. Less of a pain to install and you don't always have the sight up if you are using an optic etc.
 
I bought a AR kit from a vendor that supplied a NEW US made barrel. It was in the white and not drilled for the front sight....I basically tapped the pin holes on the front sight base. Forget the size at the moment. once I did that and was happy with the position of the front sight I dimpled the barrel through one of the holes.
I used a tap I had on hand and the set screws where cheap. A lot easier than trying to drill the barrel and useing pins. you could also drill and tap up through the bayo lug tabs and use set screws there?

just looked, I used a 8 32 tap and I think the set screws where 3/16 or maybe 1/4 long. If you have to buy taps and drill bits might be cheaper to just buy a clamp on A2 sight base one from armalite was 45$ last I checked ? It worked well for me and it never shifted. I blue loctite the screws. I have since sold that AR and have never heard back from the buyer with any issues.

http://www.gswagner.com/arsight/arsightmods2.html here is where I got my info
 
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I bought a AR kit from a vendor that supplied a NEW US made barrel. It was in the white and not drilled for the front sight....I basically tapped the pin holes on the front sight base. Forget the size at the moment. once I did that and was happy with the position of the front sight I dimpled the barrel through one of the holes.
I used a tap I had on hand and the set screws where cheap. A lot easier than trying to drill the barrel and useing pins. you could also drill and tap up through the bayo lug tabs and use set screws there?

just looked, I used a 8 32 tap and I think the set screws where 3/16 or maybe 1/4 long. If you have to buy taps and drill bits might be cheaper to just buy a clamp on A2 sight base one from armalite was 45$ last I checked ? It worked well for me and it never shifted. I blue loctite the screws. I have since sold that AR and have never heard back from the buyer with any issues.

http://www.gswagner.com/arsight/arsightmods2.html here is where I got my info

Thanks for the info!!!

That's a great idea. Drilling and tapping are not a problem for me. Should have everything I need at my work....
 
Thanks for the info!!!

That's a great idea. Drilling and tapping are not a problem for me. Should have everything I need at my work....

Advantage is you can also zero your rear sight dead center by zeroing the windage with the front sight. I zeroed at 25 yards for windage. Centered rear windage and moved the front sight until windage was zero. front sight is moved opposite if you need to move impact right you move front sight base to left. It doesnt take much to move the POI.
 
I've used the Armalite one piece clamp A2 FSB on a couple of builds for exactly this reason. Pinning a FSB is one of the few tasks on an AR15 that might qualify as gunsmithing.
 
I've used the Armalite one piece clamp A2 FSB on a couple of builds for exactly this reason. Pinning a FSB is one of the few tasks on an AR15 that might qualify as gunsmithing.
Especially when your done and it's canted......time for some smith'n now.....!
 
If you want to do it with the taper pins, Mike from Nodak Spud put together a picture tutorial on arfcom showing how to do it. You can see it here:

http://www.ar15.com/forums/t_3_123/470461_.html

Thanks! Gonna check this out...

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I've used the Armalite one piece clamp A2 FSB on a couple of builds for exactly this reason. Pinning a FSB is one of the few tasks on an AR15 that might qualify as gunsmithing.

Where can you find the Armalite ones??
 
I did it once just to do it. It wasn't particularly hard to do, just go really slow with the reamer. (It goes faster than you might think.)

To get it aligned properly, I tapped the hole under the sling mount and put in a set screw. Then I went to the range and got a good zero and tightened the set screw. Luckily nothing moved when I drilled and reamed the base.
 
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Advantage is you can also zero your rear sight dead center by zeroing the windage with the front sight. I zeroed at 25 yards for windage. Centered rear windage and moved the front sight until windage was zero. front sight is moved opposite if you need to move impact right you move front sight base to left. It doesnt take much to move the POI.

I did the same thing with the front sight mounted on my gas block rail. I just loosened the block screws and rotated it until zero on the rear sight was zero for the rifle.
http://www.armalite.com/ItemForm.aspx?item=EU0236KIT
I prefer not to mess with the barrel if I can avoid it.
 
If you want to do it with the taper pins, Mike from Nodak Spud put together a picture tutorial on arfcom showing how to do it. You can see it here:

http://www.ar15.com/forums/t_3_123/470461_.html


That's a good tutorial - it's a little easier with a new FSB. A new FSB won't have the holes drilled for the pins, or have the sling swivel installed. There's a hole under the sling swivel mount that can be tapped and allen screwed to lock the base on the barrel while drilling, although you should still finish one pin before starting the second. Without the previously drilled holes in the used FSB shown, the drill won't walk away from the curve of the barrel. It will be just like drilling into a solid piece.

Also, the pins are a standard 2/0 pin - 7/8", IIRC. If your local Fastenal happens to have an open box, that's the way to go.

http://www.fastenal.com/web/products/details/69013

Can't remember where I got the reamer. It's one of the better quality cheap Chinese ones, if the pro machinists will let me get away with that oxymoron. Treat it well and use cutting fluid!
 
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