FSB vs Rail mounted Sight [Archive]

JonnyVain

03-01-10, 12:41

What are the drawbacks and benefits of a barrel mounted front sight base vs a rail mounted fixed front sight? Is the influx of rail mounted sights a direct reflection of the influx of electronic optics?

I would think the barrel FSB would inherently be more accurate.

I have a Troy 2 piece rail which clamps onto the barrel extension. My optic is Primary Arms, so I consider my irons to be my main sight.

Belmont31R

03-01-10, 13:38

Low profile, and allows you to get a longer sight radius if your rail goes past the gas block. I like 12 o'clock mounted white lights so I can have a light where I want it without a FSB getting in the way.

Traditional front sight bases are very durable and pretty much bomb proof. Also quicker to switch to the BUIS since you only have one sight to deploy not two.

I only have 2 AR's with traditional FSB's anymore....but will be adding a 3rd when the BCM 14.5" middy comes out.

JonnyVain

03-01-10, 14:43

Low profile, and allows you to get a longer sight radius if your rail goes past the gas block. I like 12 o'clock mounted white lights so I can have a light where I want it without a FSB getting in the way.

Traditional front sight bases are very durable and pretty much bomb proof. Also quicker to switch to the BUIS since you only have one sight to deploy not two.

I only have 2 AR's with traditional FSB's anymore....but will be adding a 3rd when the BCM 14.5" middy comes out.

So do you have to put your front sight down to use your light? Pic?

I'm getting a dissy style barrel, so I'll have full sight radius anyway, but that is a valid point I didn't think about in my little world.

Reddevil

03-01-10, 19:19

So do you have to put your front sight down to use your light? Pic?

I'm getting a dissy style barrel, so I'll have full sight radius anyway, but that is a valid point I didn't think about in my little world.

On the rails, you can put the light in front of the front BUIS. If you have a fixed FSB, you can go a different route.

http://img.photobucket.com/albums/v646/symr00/DSCI0002-5.jpg?t=1267492218

http://img.photobucket.com/albums/v646/symr00/DSCI0003-5.jpg?t=1267492298

JonnyVain

03-01-10, 19:40

Ok. So you'd have to lose sight radius to do that on a rail.

So any drawbacks to mounting the sight on your rail, besides rezeroing if you remove the rail?

goodale

03-02-10, 09:56

hey reddevil, who makes that light mount you have? i like it a lot

Norsemen

03-02-10, 20:23

Another option

http://i960.photobucket.com/albums/ae86/norsemen_photos/Hobby/AR2.jpg

Surf

03-03-10, 01:10

If the rail for some reason gets a good blow and happens to shift, then your irons are SOL. While sight radius is a valid concept, carbine length FSP vs a a couple or so more inches on a rifle is not as big of a factor in my book.

Personally for a duty carbine that may see some up close hard contact, I like a good pinned FSP. For precision rifles or SPR's, we need to balance use / needs etc, so I am not as inclined to be as picky.

Just my preferences.