Installing a FSB - Page 1

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Posted: 4/28/2016 9:07:31 AM EDT

I have an old S&W M&P15 upper that has the picatinny gas block. I would like to install a FSB. Will the barrel notch that was made when the gas block was installed line up and work with a FSB?

Posted: 4/28/2016 9:16:04 AM EDT

[#1]

Probably not. If it does, it's just a coincidence.

FSB's are installed by drilling the barrel and FSB at the same time. It's basically a matched set. Your best option is to send it to a good gunsmith and let them do it. The odds of being able to reuse the previous pin holes are pretty slim.

Posted: 4/28/2016 9:23:30 AM EDT

[#2]

I've dealt with them on occasion, As stated, it most likely won't line up.

I've actually sworn off working on them, it can be a nightmare. If I need FSB work done, I just send it off now.

Posted: 4/28/2016 9:46:47 AM EDT

[#3]

Easier to sell the existing barrel and buy a new one with a FSB.

Posted: 4/28/2016 10:59:57 AM EDT

[#4]

Not trying to hijack, but I'm in a similar boat. Barrel is drilled for pins, but my FSB has set screws. Are my options basically just run the set screws or buy another one?

Posted: 4/28/2016 1:21:28 PM EDT

[#5]

Send it to forum member John Thomas.

He has a jig that aligns the FSB perfectly TDC as well.

Posted: 4/28/2016 1:43:43 PM EDT

[#6]

ADCO is the answer here. Do it right the first time they are not expensive, great quality work, and carry a good reputation around here for a reason.

Posted: 4/28/2016 3:42:05 PM EDT

[#7]

Another option is to buy Armalite's National Match windage adjustable clamp on front sight base. It just slides on the barrel and you can tighten it exactly left/right to get a perfect mechanical zero on the rear sight.

Posted: 4/28/2016 6:20:03 PM EDT

[#8]

It's not going to work with the existing pin notch. Besides, a FSB requires two notches. ADCO is the answer.

Posted: 4/28/2016 8:28:04 PM EDT

[#9]

You need a new undrilled FSB. ADCO installed one for me on a barrel that had already been drilled

Posted: 4/28/2016 8:28:55 PM EDT

[#10]

Quote History

Quoted:
ADCO is the answer here. Do it right the first time they are not expensive, great quality work, and carry a good reputation around here for a reason.

View Quote

correction: a GREAT reputation!

Posted: 5/2/2016 2:13:53 AM EDT

[#11]

Quote History

Quoted:
Another option is to buy Armalite's National Match windage adjustable clamp on front sight base. It just slides on the barrel and you can tighten it exactly left/right to get a perfect mechanical zero on the rear sight.

View Quote

Discontinued

Posted: 5/2/2016 7:51:32 AM EDT

[#12]

Quote History

Quoted:

Discontinued

View Quote View All Quotes

View All Quotes

Quote History

Quoted:

Quoted:
Another option is to buy Armalite's National Match windage adjustable clamp on front sight base. It just slides on the barrel and you can tighten it exactly left/right to get a perfect mechanical zero on the rear sight.

Discontinued

Love those things.

Posted: 5/2/2016 8:55:26 AM EDT

[#13]

Quote History

Quoted:

Another option is to buy Armalite's National Match windage adjustable clamp on front sight base. It just slides on the barrel and you can tighten it exactly left/right to get a perfect mechanical zero on the rear sight.

View Quote

That seems to never be in stock.

Edit: Discontinued would be a good reason it's never in stock.

Posted: 5/2/2016 9:46:05 AM EDT

[#14]

Send it to ADCO to have it done right and pinned to the barrel.

In a pinch you could use a WOA set screw FSB: https://www.whiteoakarmament.com/xcart/product.php?productid=17819&cat=256&page=6

Posted: 5/2/2016 1:10:05 PM EDT

[#15]

Quote History

Quoted:
ADCO is the answer here. Do it right the first time they are not expensive, great quality work, and carry a good reputation around here for a reason.

View Quote

I second this, ADCO does great work , they are fast and reasonable

Posted: 5/2/2016 1:59:58 PM EDT

[#16]

I posted in 'build it yourself' and above here. Here's my situation that's in this vein. I have a PSA barrel that was sold with a pinned FSB, but sold to me stripped. It's a new barrel, but the FSB I have has set screws. They seem to line up close with the pin holes and thread into them. Red loctite and be done or try and have it matched up and pinned?

Posted: 5/2/2016 6:45:40 PM EDT

[#17]

I bought a clamp-on FSB to finish a spare parts-build:
http://shop.deztacticalarms.com/A2-Fixed-Front-Sight-Clamp-on-750-w-Bayonet-Lug-DEZ-1035-GB.htm

Although if you already have a gas block, it might be cheaper to have a local gunsmith install it for you.