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 Pros and Cons: Free float rail handguard vs regular rail handguard
mauiblue  [Member]
8/19/2007 10:11:37 AM
I'm hoping some members would express their opinions about free float one piece rail handguards versus regular rail two piece handguards (like the Surefire M73). Right off the bat, I figure the two piece rail handguards would be easier to install and are less expensive. Free float one piece would be a bit more involved in installing them but what would be a positive side of having a free float rail handguard? Mahalo in advance.
Stickman  [Industry Partner]
8/19/2007 10:45:57 AM
There are a lot of rails to choose from, and you can get a FF rail that is one or two piece. Below are two links that show the installation process of a one piece, and a two piece rail (both are free floating rails). The first is the Midwest Industries MI-20 rail, and sells for a little under $165. The second is the Daniel Defense 7.0 Lite rail. This is a lighter, slimmer rail, and sells for a little under $310.

Midwest Industries Rail install and pictorial review

Daniel Defense Lite Rail install and pictorial review

Non-free floating rails are available as well, but quality ones are aren't all that much cheaper than the FF rails.



As for the differences between FF and non-FF rails, the easiest definition would be that one touches the barrel and can have an impact on accuracy, and one doesn't. How much real world difference it makes can be harder to judge. A FF rail allows a shooter to mount items on the rail, and not have them shift, wiggle or move around when pressure is applied to the rail. The non-FF rails are known to move when pressure is applied, and over time they tend to increase the amount of play as the spring inside the delta ring assembly compresses. FF rails are solid, and won't move.

Accuracy can be increased with a FF rail, but for many shooters who don't shoot at long distance, it won't be something that is really noticed.
CWDraco  [Member]
8/19/2007 10:53:10 AM
From what I have heard the only real benifit to FF is accurancy, everything else is either very minamal or myth. And the accuracy you are gaining isnt anything huge over a well made upper. The heat factor ppl talk about is for full auto, over extended timeframes.....

I will say this, I have never invested the time to check for myself.

I do beleive if you are going to hang optic gear off the front of the weapon, its best to go with a good solid FF.
swhitney  [Member]
8/19/2007 5:02:38 PM

Originally Posted By mauiblue:
I'm hoping some members would express their opinions about free float one piece rail handguards versus regular rail two piece handguards (like the Surefire M73). Right off the bat, I figure the two piece rail handguards would be easier to install and are less expensive. Free float one piece would be a bit more involved in installing them but what would be a positive side of having a free float rail handguard? Mahalo in advance.


Chicks Dig FF rails way more than snap in clamshells...

You will get more chicks and they will be better looking...

FF = MP

Ironcross  [Member]
8/20/2007 10:47:25 AM
The biggest "pro" of a 2-piece unit is obviously the ability to install it asap as soon as you get it. Which is great for me as I'm a "instant gratification" and impatiant type.
Though the FF=MP is very tempting.
mauiblue  [Member]
8/20/2007 12:32:32 PM
Okay, my newbieness curiosity piqued...wtf is *MP*?!?!?!?!?!
Ironcross  [Member]
8/20/2007 8:39:20 PM
MP: More P*&$%
mauiblue  [Member]
8/20/2007 8:57:06 PM

Originally Posted By Ironcross:
MP: More P*&$%


Mahalo for the enlightenment! hehehe!
Squ1ggy  [Member]
8/22/2007 2:33:45 PM

Chicks Dig FF rails way more than snap in clamshells...

You will get more chicks and they will be better looking...

FF = MP



LOL -

I have FF Rails and standard handguard setups.

FF is nice, but a $10 rail on your standard handgaurd also works pretty well.

If you have the cash to go FF, I would do it.(Even my chick likes them- and she hates
guns )

just my .02

Squ1g


Alpha-Romeo3  [Team Member]
8/22/2007 5:51:35 PM

I've got both handguards, here's my LaRue 9.0 one piece FF handguard,




and my KAC M4 RAS two piece non FF handguards


I like to have the FF type for slightly better accuracy for longer range shots, but they're more involved in installing yourself, you would need tools like an upper receiver action block, FF installation wrench and some kind of either a medium or large table shop vise.

I prefer the LaRue or the Daniel Defense Lite series FF rails because they have a locking design that prevents the handguard from getting loose from the mounting, which is the main problem of regular FF rails without a locking design.

For close work I don't really need the FF type and I'm satisfied with my two piece drop in rails (special tools not required).

I would recommend getting the KAC M4 RAS or something equivalent that have a locking bracket inside that locks to the barrel nut, it prevents the rail from moving, if you look in the Equipment Exchange sometimes you could get it at a good low price.
nhsport  [Team Member]
8/22/2007 6:18:45 PM
I have felt that the whole free float thing is partly a gimmic. In a competition gun where somebody is putting heavy preasure on the sling and shooting 400 and 600 yards it is desirable (although plenty of military target shooters do without with good results ) .
I have one on my RR service rifle becaues that is the way it comes but truthfully I am only shooting reduced courses (reduced targets at 100yds ) so the real life difference is about nothing .
The average guy building up a general purpose rifle or one that might see some kind of three gun use on plates out to 150 yards isn't going to know the difference although FF is all the rage.
On the other hand it isn't going to hurt anything but your wallet so why not?
tweeter  [Team Member]
8/24/2007 10:11:41 PM

Originally Posted By CWDraco:
From what I have heard the only real benifit to FF is accurancy, everything else is either very minamal or myth. And the accuracy you are gaining isnt anything huge over a well made upper. The heat factor ppl talk about is for full auto, over extended timeframes.....

I will say this, I have never invested the time to check for myself.

I do beleive if you are going to hang optic gear off the front of the weapon, its best to go with a good solid FF.


Did you actually read this after you wrote it? Accuracy and reliability are the only real reasons to adjust anything on your weapon. And you're downplaying accuracy?

Barrel tension from a sling or rest is neither minimal (whatever that was supposed to refer to) and it certainly isn't myth. Have someone with a regular forward slung weapon turn a sling around their hand and then have them do it with a floated barrel. You'll see a definite difference at realistic ranges (even as close as 200-300 yards). With a floated barrel you can still keep that tight position on your sling and not inconsistently affect your barrel harmonics.

No, barrel harmonics aren't an abstract, they're very real.

Heat is real too, try holding on after about two strings of 9 shots each and see where you naturally want to put your hand to support the weapon. And this could be after walking around in full summer sun with a black metal weapon, you're just gonna ramp up the level of heat by firing, even a little bit.

Optical gear isn't usually put on the front of the weapon unless it's a night-vision tube to amplify a day-only telescopic sight. What is usually put up front is bipods, lights, lasers, switches, grips and swivels. Some of that stuff gets pushed or pulled pretty well in a stressful situation... you don't want it to throw your aim off when you start pulling and pushing on parts of your gun.
Falar  [Member]
9/3/2007 8:52:01 PM
I've used 1 piece FF handguards before and didn't like them as far as cleaning your weapon goes. In dusty environments a lot of dirt will build up around the barrel since the cooling vents will let just about anything in. To get all of that crap easily you would need to take off the handguard. I've recently acquired a new Bushmaster M4A3 and am really leaning towards getting either the KAC M4 RAS (if I can find one at a good price) or an MI 2 piece. As much as I like to do anything possible to increase accuracy I don't know if the extra "hassle" is worth it, especially if the gain is marginal at best. Now if anyone has evidence to that contrary that a FF handguard will greatly improve accuracy then please shime in. I am concerned that a non-FF 4 rail handguard may have issues with lasers holding a zero, however. Can anyone chime in on that?
clasky  [Team Member]
9/6/2007 8:32:46 AM
Usually, the FF handguards are going to be a bit more solid with no movement. Some 2-piece guards, like the KAC RAS and RASII will be just as solid, though, because of the way they lock to the barrel nut. As for accuracy: the improvment of a FF will most likely not be noticeable to the average shooter.
jason_h  [Member]
9/6/2007 3:54:35 PM
It isn't so much accuracy as the shift in the POI when using a vert. fore grip, sling, or bipod. I can cause my cold M4 profile barrel to deflection noticeably under only thumb pressure. Lightweight barrels don't need much to cause them to bend. Add a couple mag dumps and barrel deflection is even more pronounced.

With all the FF options on the market now, it just doesn't make any sense to go with a non-FF handguard. Heat is not only an issue with FA. When the temp is over 90F, even one mag will make the barrel hot enough to make throat erosion an issue over time. The cooler your barrel stays the happier it will be. This means less stringing and longer barrel life.

If cleaning the outside of your barrel is an issue, get a 2 piece unit like the troy/sampson, etc. handguard.
mauiblue  [Member]
9/6/2007 5:50:02 PM
I thought about the cleaning issue with FF handguard but oh well. I don't roll around on the dirt or grass when using my Bushmaster Modular carbine and it is not very dusty where I shoot. If need be, I could stick a thin rag in between the barrel and the FF using a small dowel. I am enjoying my Bushmaster with the FF but I will leave the RRA Entry Tac with the M4 handguauds alone. The VFG on it is enough for me.
2nd_amandment  [Member]
9/6/2007 6:37:13 PM
The FF has an advantage that hasn't been mentioned.
On a FF rail, the optics can be mounted forward of the receiver, an Eotech buttons for example can be reached easily with the thumb of the hand that holds the forward grip.

Holosights are meant for both eyes open shooting, and with 1x magnification, the eye relief and field of view is out of question, which means the farther mounting of the holosight will definitely provide better target acquisition, except for the night vision which requires the view thru the site only.

The snap-on handguards have a movement, so it defeats the purpose of having the optics such as holosights or lasers on them. Even a forward grip feels funny when it doesn't feel solid.

However if one doesn't want any optics or lasers mounted on the rail forward of the receiver, then any handguard will work.

I regretted getting a snap-on rail, my next upgrade will be a FF rail.
mark5pt56  [Member]
9/6/2007 10:09:16 PM
I can tell you this much, at 100 yards, with my g profile 20"(standard hg's) I pulled 2 shots into the 5 ring while prone. I had the green web sling and had it a bit tight. I realized what I was doing, loosened it some and they came back into the center. W/o measuring, that was about 3-4 inches.
PALADIN-hgwt  [Member]
9/7/2007 6:52:22 PM
When I shot this 200 yard group using a non-free floated barrel and standard M16 handguards the whole SPR craze started to sound, well, just crazy man.

Paladin