FSB not lining up?

[sullyxlh]

Got an FSB for my AR brl and it's not lining up in the mounting holes,
It's a new never installed FSB,it's marked F on one side and BOM on the other and the brl is a Colt and was manf. 10/04
Did I get a bad FSB? or an Airsoft maybe.......
Can't imagine the brl being in error...
Thanks

http://i159.photobucket.com/albums/t160/sullyxlh/DSCN0095.jpg

[Joeywhat]

I can't see the pic (work), but is it secured by taper pins going through the barrel?

You can always get a FSB that uses set screws...

[sullyxlh]

I can't see the pic (work), but is it secured by taper pins going through the barrel?

You can always get a FSB that uses set screws...
Right
but if you were to put one pin in the other would not line up it's close but not to where you can get the other pin in.

[Pnab]

Since FSB's are independently drilled and taper pinned per each barrel, just swapping out a New FSB from the old one is not an easy task. The new FSB would need to be drilled to match the old barrel taper pin slots in the barrel, and indexed for the correct barrel index alignment with the centerline of the barrel extension.
The "F" stamp indicates that the height from the barrel to the location of the pin is 1.98" oppossed to a standard FSB which is 1.94"

[JohnJak]

What brand is the FSB?

[sullyxlh]

What brand is the FSB? Not sure
these are the casting marks on the other side
http://i159.photobucket.com/albums/t160/sullyxlh/DSCN0101.jpg

Pnab,
By the sounds of the way you put it
I probably should have looked for a Colt FSB as opposed to any FSB
Is there a different measurement btwn a milspec barrel and non milspec brl?

[Knimrod]

Moved to DIY Gunsmithing - Admin

[sullyxlh]

Thx!
My bad..
:salute:

[Joeywhat]

I agree with the above post...if it's using taper pins it probably won't line up. You'd have to drill the holes yourself. That is why if I were to get a new FSB/gas block, I'd just get an "adjustable" one that uses set screws or tightens areound the barrel. My first RRA had that...just two allen heads that wrapped the block around the barrel, you could line it up just right before tightening.

[sullyxlh]

I agree with the above post...if it's using taper pins it probably won't line up. You'd have to drill the holes yourself. That is why if I were to get a new FSB/gas block, I'd just get an "adjustable" one that uses set screws or tightens areound the barrel. My first RRA had that...just two allen heads that wrapped the block around the barrel, you could line it up just right before tightening. Thanks Joey,
I was hoping to find something I wouldn't have to mess with and don't want to go the SS route on a front sight if I don't have to
I see nightmares even thinkin about having to send my brl off to get an FSB drilled...
Is there a Military Specification measurement for this or
Is thinking an FSB from another Colt barrel would fit out of the question?
I'd like to run the traditional A tower but if it's too much trouble
I'd probably go with something like the PRI flip up FS or something similar..