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Anyone know how to install an FSB on an AR15?

ntomsw

ntomsw

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As the title says, I am looking to see if anyone knows how to properly install a front site base/block on an AR15. I bought one the other day, but now need someone to install it. I was talking to another NES'er yesterday, and he told me about Greg Derr, which I have emailed. I have also emailed Business End Customs as well.

While I wait for their responses, I figured I would ask if someone on here knows how to drill and mount one.

It is an F marked FSB, going on a 16" M4 barrel with a carbine gas system. I have the stripped upper, barrel, delta ring kit, round hand guard ring, carbine gas tube and roll pin, and the FSB. I just need the sight installed.

If anyone 'local' to Worcester knows what they're doing, let me know. As far as compensation we can work something out. My company should be good enough. [laugh]

It is this site:

STCK0641-1024-Stick.jpg
 
The barrel is NOT drilled for the FSB and I do NOT have taper pins for the FSB.

I have everything else.

- - - Updated - - -

Site needs to be drilled as well.
 
Is the front sight drilled already? I purchased a kit that came with a barrel in the white and not drilled for the front base either. Now paying to ha e the work done was against this build plan of being low budget.
so I went with this A2 GUN CLAMP-ON SIGHT KIT
Which I will be needing another for a 22lr AR build....
You may want to poke around on the rifle competition section lots of ar shooters
also maybe noha's motors. In sagus?
 
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Front site is NOT drilled.

People on NES build guns out of shovels. There must be someone here who can do this professionally. [laugh]
 
The traditional method of attaching a front sight block (more commonly referred to as the sight tower or gas block, since it must have the gas system, but there are models without the front sight) is to drill the holes for the taper pins while the block in place - not a job for an amateur. It's virtually impossible to drill holes in a block to match existing holes, although there are probably people who could do it. Boris could probably do it with a hand powered drill.

Other gas blocks attach either with retaining screws in the bottom of the block, or bolts on the side that clamp the block in place (these don't mark up the barrel like the former). If you are doing your own build, or replacing an existing gas block, one of these is your best bet.

Taper pin gas blocks can do a better job than screw pin gas block of holding the block in place during extensive full auto fire, but other than that, that the clamp on gas blocks are excellent. Here is one example if you want a sight tower as part of the block:

JP Rifles

And an example for a flat stop/scoped rifle:

JP Rifles
 
Well, I already have the site, so I don't want to be buying anymore different sights.

The FSB that I bought is not drilled or anything. It has the hole for the gas tube and the hole for the gas port on the barrel but that's it. I like the style I bought it has the adjustable sight built into it.

If no one here can do it, I'll just have Greg Derr or BEC do it, once they get back to me.
 
chinalfr said:
Have you try Greg @ PAW?
Click to expand...

No. I don't know who does this stuff, or who is going to do it properly.

I figured someone on here could do it, but I guess not. No big deal. It needs to get done, so the search continues. I just don't want to pay 4200 to install a sight.
 
ntomsw said:
No. I don't know who does this stuff, or who is going to do it properly.

I figured someone on here could do it, but I guess not. No big deal. It needs to get done, so the search continues. I just don't want to pay 4200 to install a sight.
Click to expand...

4200? You can only get a glock nowadays.

Sent it from iPhone 5 LTE
 
chinalfr said:
Free float the handguard and get a lopro gas block.

Sent it from iPhone 5 LTE
Click to expand...

Too late. I already bought the hand guard I want to use, site I want to use, etc etc.

I already have 1 AR with a free floated hand guard. I wanted something different this time.
 
chopper_man said:
What about John? I'm thinking of doing another trip real soon. Need to get a brake pinned and welded.
Click to expand...

Yeah I was there again Saturday to buy the sight, but he didn't have time, and I forgot my gas tube, so he couldn't do it anyway. They have no more carbine gas tubes, so I couldn't even buy one.

So yeah, I am an idiot. It would have been done right now, if I remembered the gas tube.
 
YouTube

This is all I found. I would be interested in seeing the proper jig used by manufactures though.

The gas tube is a easy install. ...I'm tempted to try this install myself. If I ever get a budget barrel and sight again...I see several ways to do this on the hack it yourself (DIY) but I wouldn't try on a quality build.
 
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Front sights are easy to install as long as you have the right combination of sight/gas block and barrel. If you have the stock sight that requires tapered pins and a pre drilled barrel but also have an untouched (drilled) barrel you are in need of either professional help or a new front sight/gas block.

My favorite is the front sight/gas block made by ARMS. This sight clamps on to the barrel rather than using the tapered pins. The sight is a dead ringer for the stock model but folds down out of the way for the use of optics and it even comes with a removeable bayonet lug for you macho types. Not cheap at $130 but well worth it IMHO.
 
PS If your barrel isn't drilled for the pins necessary to instal a stock FSB, you would be better off buying a new FSB rather than altering the barrel.
 
So, because by barrel isn't drilled for it, I need a new sight?? Huh?

A gunsmith should be able to do exactly what I need. I'll just wait for Greg Derr's response to my email. He is very far from me, but I need it done.
 
ntomsw said:
So, because by barrel isn't drilled for it, I need a new sight?? Huh?

A gunsmith should be able to do exactly what I need. I'll just wait for Greg Derr's response to my email. He is very far from me, but I need it done.
Click to expand...

I think this is your best bet. In order to get it set nice and square you'll need the proper drill etc... You run the risk of drilling into the barrell if you don't do it right. Better to be patient. I wouldn't hesitate to let Der or bec work in anything I owned, they both have a great rep. Call Pullman? Perhaps they can too they have a machine shop after all.
 
Yeah, I am headed to Pullman now. They are 20 seconds from my house. I called them and they told me to bring the parts in to see what I want done. Hopefully they can do it, and do it cheap. I don't want a stupid site base costing $200.
 
you have to shim the space in back of the sight for the hand guard cap. have them set it up that way ,if you decide to go with stock handguards .

and put your barrel nut on first as well.
 
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The barrel is already installed. I will be bringing them the hand guard cap, and FSB to have them install it. And gas tube/roll pin.
 
also PM Warwickben, pretty sure he's a machinist ? Lots of guys here are good with their hands. If it were mine & I had a bridgeport, I'd do it myself, but neither are the case.
But also I hate my pyramid gas block sight. I prefer the flip-up BUIS. When I have the money I'll be changing it over to a 45-degree back-up iron sight.
 
why don't you just drill the barrel for the pins? You know- with a drill press and a bench vise?

take a pair of vice grips, wrap them in tape, then fabric, and clamp the FSB in place to the barrel.

Square it up to the drill press in a bench vise.

Select the correct diameter drill bit.

Put it into the drill press.

Turn it on (low speed.... 150 RPM, or maybe even 200?)

Crank it down. Remove material in barrel using FSB holes as guides.

Ease off once the material is gone.

Then do the other hole.

drilling a barrel isn't going to magically make your gun inaccurate. It's not going to **** it up if you do it right. And it's not difficult. For christ's sake, I drilled pin slots in a AK barrel with nothing more than a hand drill, a bench vise, using my hands to stabilize the hand drill. A drill press will help you be true to the barrel.


What part of "DIY" do AR-15 fanbois not get? Were you guys born with vaginas or did you grow them after buying your rifles?


JESUS CHRIST.
 

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