Choosing Rail System

[ForceFed4g63]

My father in law got me a gift card to Brownell's for Christmas for a rail system. I'm going to get a free floating quad rail, or possibly a free floating tube. My question is, is there anything special I need to know before I order? What's the longest I can get for a standard 16" barrel?

[Bradleyrj]

You can put a 15 inch if you have a low profile gas block if not get one of those also. I hate "quad rails"... They are very uncomfortable to shoot in my opinion. Even with the hands guards on the rails that T being used to mount an accessory. I personally like the key of stuff because it's typically smooth around the 90% of the hand guard with the rail only on the top and anything Samson makes.

[Bradleyrj]

^ Assuming you have a standard front sight post... You'll need the Lopro gas block of course.

[ForceFed4g63]

How do I check to see if I have a low profile gas block? I'm still a gun n00b. I don't really want a quad rail either but I'm leaning towards a rail with keymod features on the bottom and sides and a rail on top.

[Bradleyrj]

This is a standard front sight post with the gas block built in. The gas tube runs from here to the receiver to make the bolt cycle.

http://i99.photobucket.com/albums/l289/BradleyRJ/Hunting/60B6EA83-04DF-42C8-A7F8-6C19ED02B90A_zpsk7e573ey.jpg (http://s99.photobucket.com/user/BradleyRJ/media/Hunting/60B6EA83-04DF-42C8-A7F8-6C19ED02B90A_zpsk7e573ey.jpg.html)

Here is a standard sight post that has been cut off. You can do this but you'll still need to pull it off the barrel so that a few of the "drop in hand guard" pieces can be removed. Reinstall and use basically any rail you want and it covers it up.

http://i99.photobucket.com/albums/l289/BradleyRJ/Hunting/7CC27BEF-1EF1-4EE4-8B12-C6E6F0906E4D_zpsmxn2qzyl.jpg (http://s99.photobucket.com/user/BradleyRJ/media/Hunting/7CC27BEF-1EF1-4EE4-8B12-C6E6F0906E4D_zpsmxn2qzyl.jpg.html)

Aftermarket gas block. Same as above except replaces the sight post.
http://i99.photobucket.com/albums/l289/BradleyRJ/Hunting/CFA5F35D-3AC4-42E8-80C2-D25810BE7030_zpsot6ge3ws.jpg (http://s99.photobucket.com/user/BradleyRJ/media/Hunting/CFA5F35D-3AC4-42E8-80C2-D25810BE7030_zpsot6ge3ws.jpg.html)

Also they make one that has a small section of rail on top. (These can be for drop in front hand guard or short free float rails.

http://i99.photobucket.com/albums/l289/BradleyRJ/Hunting/F2C6B1E4-5222-47B9-8C7B-132FB4D15E82_zpsbh6n96cr.jpg (http://s99.photobucket.com/user/BradleyRJ/media/Hunting/F2C6B1E4-5222-47B9-8C7B-132FB4D15E82_zpsbh6n96cr.jpg.html)

I put a low profile on mine and slinger hand guard. The last picture is a drop in style with a carbine length gas system. If you replace with a low pro gas block or trim yours down you can put a 12 or 15 inch free float hand guard on it and cover it all up. I like Samson and Diamondhead front rails. The Diamondhead comes standard on the new Ruger 556 rifles. Very comfortable.

[ForceFed4g63]

I gotcha, that makes sense, thanks Brad! Any recommendations on a low profile gas block? Might as well replace it while I'm at it. I assume that's not an expensive piece?

[94FormulaBird]

can be had for under $35 if non adjustable....make sure to get the right size inner diameter(.750 for standard barrel)...they make clamp on versions...set screw versions...depends on what you want....

I have a parallax tactical 15in ffssr(free float super slim rail) on my ar....it was pricey($200) but had a top rail and side rails at the front and slim in the middle....great to hold...
http://i77.photobucket.com/albums/j49/dragons_blood_802/7A3CFE58-5B10-4DD1-84BE-5C138F39027E_zpsnfakbnav.jpg (http://s77.photobucket.com/user/dragons_blood_802/media/7A3CFE58-5B10-4DD1-84BE-5C138F39027E_zpsnfakbnav.jpg.html)

[PapaBear]

At this point, you've decided on free float of some sort, now to decide on tube or quad.

Quad is heavier of course, and feels like a cheese grater on bare hands IMHO.

The new keymod and M-lok stuff is good, with good aftermarket support, so don't shy away from them.

As far as low-pro, just don't get an aluminum one, they tend to act up when shot enough to deform from heat (never experienced myself).

For the rail, make sure it either uses factory barrel nut, or comes with its own. For length, remember, the longer it is, the heavier it is. Take a look at some of the more expensive options, and you'll see they are considerably lighter.

Lemme know if you need help. Come by and have a beer and I'll let you use my tools to put it together.

[ForceFed4g63]

Awesome, thanks Buddy!!

[ForceFed4g63]

Ended up getting the Bravo Company KMR Alpha Rail in 13". Has tons of good reviews, hopefully it works well!


http://www.brownells.com/userdocs/skus/l_100018333_2.jpg

[PapaBear]

Perfect IMHO. 15" looks cool but that last 2" isn't very functional.

[ForceFed4g63]

Perfect IMHO. 15" looks cool but that last 2" isn't very functional.

That's what I thought as well, the 15" looks cool but I simply don't need it. Added cost and added weight.

[Bradleyrj]

Yeap. Sorry been out of town and away from life a while. Can't go wrong with the Braco stuff.