Rear sight for non F-marked FSB

[pubb]

So I just picked up a 14.5" Colt SOCOM barrel and it is not marked with an F. The brown truck o happiness has not gotten here yet.

1) if it isn't marked, might it still be an F-height? How can I tell?

2) if mounted on a flat-top upper, what would be an appropriate BUIS choice?

3) Can I just replace the front sight post, or will it stick past the protective ears?

Thanks

[26 Inf]

So I just picked up a 14.5" Colt SOCOM barrel and it is not marked with an F. The brown truck o happiness has not gotten here yet.

1) if it isn't marked, might it still be an F-height? How can I tell?

2) if mounted on a flat-top upper, what would be an appropriate BUIS choice?

3) Can I just replace the front sight post, or will it stick past the protective ears?

Thanks

1) I don't know if they are all marked. The F marked sights are 0.04 taller. According to what I have seen the distance between the barrel to the flat surface between the ears of the FSB is 1.98 on the F marked and 1.94 on the standard.

2) I have a sample of one upper with a non-F marked sight. I have a fixed Troy Battle Sight on it - works fine.

3) If need be you could replace, several places have tall front sights: https://www.knsprecisioninc.com/prod...ht-040-taller/ (pricey) https://shop.windhamweaponry.com/products/9349056-mod This one is .030 taller: http://www.jsesurplus.com/midwestind...1-1-1-1-1.aspx (least expensive)

[scottryan]

Colt doesn’t mark them with an F anymore if this barrel is less than a year old and is factory assembled.

They are still the correct F height.

You still need to use a military dimension rear sight.

[26 Inf]

Colt doesn’t mark them with an F anymore if this barrel is less than a year old and is factory assembled.

Wonder why, wouldn't the F already be in the casting?

In that case it seems like work/expense to remove it.

[scottryan]

Wonder why, wouldn't the F already be in the casting?

In that case it seems like work/expense to remove it.

The F is stamped in the forging after the forging is made. The same forging was used for F and non F front sight bases. The machining is what separates the two.

Since colt no longer makes fixed handle rifles, they dropped the F stamping.

[26 Inf]

Thanks!

[HeruMew]

Just cranked down the barrel nut on my midlength BCA 5.56.

Has a front sight base marked as <B

Not sure what that means. Looks like non f marked to me. But not sure.

Out of curiosity, if it is a non marked, does that mean KACs or Matechs won't zero without moving the sight post too much?

[Iraqgunz]

Thanks for that information.

The F is stamped in the forging after the forging is made. The same forging was used for F and non F front sight bases. The machining is what separates the two.

Since colt no longer makes fixed handle rifles, they dropped the F stamping.

[HMsailor]

i wont be suprised if a 6920 just blows up in my face.

[TexasAggie2005]

i wont be suprised if a 6920 just blows up in my face.

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