If floating the barrel makes so much difference, why aren't the guns our guys (and gals!) are using over there in the desert ALL floated? Seriously. Are you REALLY telling me that if I shoot from a bipod or using a sling from my non floated 20" A3, that it's going to change the POI THAT much? I simply can't believe it. It seems like all you "floater" people would have us believe that the receiver/barrel junction is going to flex or fall apart at any moment. These things aren't made of jello after all, right?

Okay, so Maybe I'll buy it if you're a Marine Corps sniper. In that one scenario you might gain something... but floating a short barreled M4? C'Mon!

Seriously, does anyone have any hard and fast data here? I'm feeling the pressure to float my 20" and I don't wanna! :)

I'd be curious to see some REAL scientific data. Somehow placing an upper in a vise and measuring (somehow) how much pressure it actually takes to affect the barrel/receiver juncture. Or is this even what it's all about?

Educate me!

C

Cost mostly. The military bought a shitload of non FF RAS, and still have them. And its much hardre to put an M203 under a FF rail, cause the bottom doesnt come off to let you mount it to the barrel. You also cant clean under it. I would just hose out under the rails if it got that dirty.

I think your right, FF is great for snipers or compittion shooters, but I think it is probably lost on m-4 style rifles. someone correct me if I'm wrong please.

Quoted: I think your right, FF is great for snipers or compittion shooters, but I think it is probably lost on m-4 style rifles. someone correct me if I'm wrong please.

Its still an issue if you are wrenching on the forgrip or sling. The M4 is an extremely light barrel.

didn't think about that...I've wrenched on a 20" gov profile m-16 sling pretty good and can still hit black at 500m. but I zeroed it like that too.

Im  starting to agree.  Im going to start looking for cheap railed guards.  It seems to me that most people buy they so they can say "I have free floating handguards"  I was interested in them until I found out how much they cost.  I think the effect on accuracy would be minimal.

Another thing: I have quite a few accesories that I may sight in with or without, then shoot with or without, in interesting combinations. The weight could be a factor, although I have never hung anything off of a non FF rail.

There are several inexpensive options if all you're concerned with is free-floating.  The YHM springs to mind.

Personally I'll be heading down the Troy MRF path as it is free floated, doesn't require the front sight to be removed to install, and the lower half is removable so that you can clean the barrel.  I am going to get an Aimpoint or ACOG first though, so there might be an even better option out by that time.

Unless I devoted a huge amount of time to shooting (and this is true for practically everyone), nobody is going to shoot as well as a high quality gun, regardless of if the barrel's floated or not. That said, at least for me, FF tubes make me feel better that when I miss, it is my fault. I know that if I put a gun on a bench rest, it will place every round within an inch or so, so anything outside that margin of error is all me.
On a side note, for all the ounce-nazis out there, non-railed tubes can save a bit of weight over standard plastic forends.

Quoted: On a side note, for all the ounce-nazis out there, non-railed tubes can save a bit of weight over standard plastic forends.

There are very few FF handguards that weigh less than the standard plastic forends (6.7 oz including all mounting hardward), the M4s are 8.5 oz. The only one I could find that was lighter than standard are some of the carbon fiber FF tubes.

Mostly cost and weight.

If I sling up my A2 as tight as my 16 # Service Match AR15 at 300yds my POI moves about 6" left which is well within M.O.M accuracy. Since the military doesn't really sling shoot anymore it is not that big of deal to not FF for a combat rifle.

Quoted: Okay, so Maybe I'll buy it if you're a Marine Corps sniper.

Why does it have to be a MARINE CORPS sniper?

Quoted: Quoted: Okay, so Maybe I'll buy it if you're a Marine Corps sniper. Why does it have to be a MARINE CORPS sniper?

Because we all know they are just the besthug.gif

The free floater definitely makes a difference in regards to sling loading in different positions on the firing line for small bore rifles with barrels at least as heavy or heavier than a Hbar AR. I have seen change of impact in excess of 1/2" at 50 feet when a grown man pulls the sling up tight in a match from one position to the next. This was back in the early seventies before free floating became a standard modification to those rifles, some were still clamping a muzzle band around barrel and stock, and mounting the sling to the band. On a high power rifle being shot off the bench on sand bags, free floating also lets the barrel vibrate at it's own natural frequency, which changes with different loads, and allows the barrel to be more consistant in shot placement. This (at least in theory) is partially due to the barrel being at the same point in it's vibration pattern as the bullet leaves the barrel. In my personal experience, free floating is worth far more than trigger work in return for the accuracy dollar spent, but it doesn't feel as good as a great trigger. In regards to the military rifles, these are bought for the lowest bid that meets spec, which explains a lot.  

Quoted: If floating the barrel makes so much difference, why aren't the guns our guys (and gals!) are using over there in the desert ALL floated?

It all depends on whether you're interested in minute-of-angle or minute-of-man.  It doesn't mean squat for a soldier trying to hit CM inside the effective range of .223 coming out of a 14.5" bbl.  YOu can imagine, however, that there are situations where a 1 MOA shift matters.

Since the military doesn't really sling shoot anymore it is not that big of deal to not FF for a combat rifle.

Yes they do, when qualifying on the range anyways.

Because we all know they are just the best

Damn straight

Quoted: Cost mostly. The military bought a shitload of non FF RAS, and still have them. And its much hardre to put an M203 under a FF rail, cause the bottom doesnt come off to let you mount it to the barrel. You also cant clean under it. I would just hose out under the rails if it got that dirty.

Not to mention what hanging an M-203 off your barrel will do to the POI and accuracy.



Lonny

Free floating certainly doesn't hurt but depending on how your rifle/carbine is being used it may be an advantage.  Having a rifle/carbine that's capable of MOA accuracy is definitely not a bad thing in my book.  You'll know your weapon is capable and all you have to worry about is doing your part.  It's better to have it and not need it than to need it and not have it...

One of the reasons you see many free float rails here is that certain rails are only available in free float format.   Another reason people are using FF rails is that the price difference on the highend non-FF and FF models are pretty close and in some instances like the MRF are actually cheaper.  Look at the cost of M5 RAS and compare it to MRF-R, which would you pick?

It will make a difference when using a sling, bipod, or even benchrest/sandbag shooting, if you tend to pull on the gun or add pressure on any of these items.

Regarding the military not using them much(yet), they are using them, but are changing over from the older stuff slowly. Also, the military does not have "the best" stuff all the time. They only have the "best stuff" that the procurement boys are willing to pay for. There is alot of stuff available that is not military issue, that is very good, if not even better than the military issues to the troops.

I have both FF and un-FF.

I look at the point of the rifle that I am building.

For example, I have a post about the Predator FF forend right now b/c I want to build a 20" 6.8REM precision rifle. It will be 20" and capable of firing a heavier bullet so it makes sense.

I also have an M-4 w/ an aimpoint. I have like no chance of using that sight at point targets over 400M- it is not free floated.

If your rifle is for highpower or it is scoped- FF.

If it is for plinking or up close combat- you are wasting your money. You would be better off spending the money on ammo to get better at shooting.

I FF everything because I have money coming out of my wazoo.

Free floating can make a difference.  I have not experienced this with an AR, but have personally seen the effect a little barrel pressure can have on other firearms.

There are two scenarios I have encountered that  have resulted in a POI shift.  One is bottom pressure:  Some rifles, including a Model Seven I have, experience a significant change in POI (on the order of 1.5").  I've seen this with a Winchester Model 43.  Shifting from a hold with the hand near the action to some sort of field expedient rest (or harris bipod) nearer the barrel will shift POI.  Is a 1.5 MOA poi shift significant?  It is to me....

The other scenario, which seems to have greater effect, is the use of a sling.  I doubt many people use a sling for added stability anymore, except for the CMP/High Power crowd.  However, if you are in the habit of using a sling for added stability, the lateral pressures can and will often shift POI.  Is this significant?   It is to me.  Others may not think so...

There is one thing to remember:  Many people seem to think that is our boys in Iraq are using something, it must be the best darned thing.  Conversely, if they are not issued "it", it probably is not worth having.  I do not buy into this line of thought.  A lot of the stuff issued to our men is issued on the basis of cost, or on the basis of other political considerations.  Need some examples?  There is tons of outdated crap still in use, mostly because budgets do not allow for equipment replacement.  And out Fort Drum service men spend considerable amounts of personal money buying various equipment items because they cannot get the "good stuff" through regular channels.


We all know about the early m16 problems with the lack of a chromed chamber.  That was a political & cost decision that fielded a substandard piece of equipment.  And we adopted a 9mm service handgun for political reasons, despite considerable evidence that larger caliber sidearms are more effective.  How of our people went to Iraq without body armor?  One could argue that because some people were not issued armor, armor must be unnecessary...

If its gonna be my equipment I prefer to think for myself instead of letting some government bureaucrat make decisions for me.  Just my two cents.

Quoted: If floating the barrel makes so much difference, why aren't the guns our guys (and gals!) are using over there in the desert ALL floated?

Actually, the requirement for SOPMOD II is that the barrel is free-floated by the new rail system. I believe this is also a requirement for the SCAR proposal.

Seriously. Are you REALLY telling me that if I shoot from a bipod or using a sling from my non floated 20" A3, that it's going to change the POI THAT much?

Depends on how far you are shooting and how big the target is. If you are shooting E-silhouettes at 100yds, then it isn't that big of a difference. If you are shooting at a partially exposed target from only 30-40 yds, it might be. If you are shooting at a semi-exposed target at 300yds, it will be,

I simply can't believe it. It seems like all you "floater" people would have us believe that the receiver/barrel junction is going to flex or fall apart at any moment. These things aren't made of jello after all, right?

I don't think barrel flex is the real issue, rather I think that free-float tubes allow the barrel to vibrate the same way every time. Here is an experiment you can do to show what I am talking about: Rest your handguards on a barricade and zero it. Now shoot at the same target with your barrel resting on the barricade instead of your handguards - the zero will shift by several inches even though there is no way you are putting enough force to flex the barrel that much.

The reason behind the zero shift isn't barrel flex but the different harmonics of the barrel during a shot when it is in contact with the barricade. Even though very little pressure is being applied to the barrel, it is enough to cause a different point of impact. Traditional handguards isolate the barrel some from these effects; but not entirely because they are still connected to the barrel.

Seriously, does anyone have any hard and fast data here? I'm feeling the pressure to float my 20" and I don't wanna! :)

I added a free-float tube to my 16" and from the bench or from prone, my average 5-shot 100yd groups shrunk about 0.5" from my previous non-FF groups. From standing, sitting and kneeling I wasn't stable enough as a shooter to see a noticeable difference.

When I bought my FF tube, they were only about $25 more expensive than the non-FF rails systems commonly available. There are a lot more options out there now including even cheaper FF systems, so whether the cost is something you can justify is a personal decision. For me, I like to plink at steel from 500yds on occasion so it was definitely worth the $25.

You say if it were a big deal the military would have FF tubes on all the M4 carbines?

Hmm lets see... right now they have old-ass outdated SOPMOD 1 rails that are not FF...  TRUE.

SOPMOD 2 M4 fore-ends MUST be free floated and they are going to be selecting a new unit shortly.

Therefore all M4 carbines WILL have a FF foreend.  It just takes time to get the testing done, the units purchased and then installed on all the M4 carbines.

Does that convince you?  

Quoted: why aren't the guns our guys (and gals!) are using over there in the desert ALL floated?

Because you don't need MOA accuracy to hit a man sized target at typical combat distances.

FF for accuracy is only needed for extream ranges, or extream precision (neither of which are needed/used for the average combat soldier).

" A3, that it's going to change the POI THAT much?

Depends - what kind of barrel do you have ( HBAR vs Govt Profile)?  What kind of range are you shooting at?  What kind of precision do you expect?

I've seen deflections from Govt Profile barrels measured in inches at 100 yards - as much as 6" off at 200 yards.  For some that's not enough to worry about - for others that is way too much.

Quoted: If floating the barrel makes so much difference, why aren't the guns our guys (and gals!) are using over there in the desert ALL floated?

Because they're shooting 3MOA ammo and are trying to hold minute-of-jihadist at distances that are probably well under 200yds.  A 200yd woodchuck or 600yd MR target 10 ring need a bit more precision...

As a former service rifle guy that cut my teeth shooting an M1A and only got into the 'mouse' rifles when I switched from shooting service rifle to match rifle, the sling tension "effect"/impact/problem is real.

But...  Just to muddy the water a bit...

Do you think its the barrel youre flexing or the receiver where it contacts the barrel?

On an M1A with a standard GI barrel or an M4 or thin AR barrel, I would say yes its the barrel.

However on my Space gun witha 26 in Kreiger bull barrel, it seems to me the flex is at the junction of the upper receiver and the barrel.

In any case, it doesnt matter in reality.  FF barrels tend to shoot better the majority of the time.  Notice I said majority - I have a 10/22 that will out shoot my Kimber 82 as long as it has the ruger barrel band on!

FF'ing a barrel allows the barrel exist in a more stable, repeatable environment with less chance for outside influences that can be inconsistant (like sling tension which changes as a sling stretches, your arm swells, etc.)  Accuracy is dependant on doing the same thing, exactly, over and over again.

Wow. Great responses, as I expected. I appreciate everyone's input and opinions. I have to say, I love the look of the FF railed forends, and I'll likely build an accurized upper with one (eventually). But, part of me is a minimalist who simply wants a combat-ready and proven rifle should I ever need it (and unfortunately, i don't think the world is going to get any better anytime soon; not to be an alarmist). As much as I'd love to throw a bunch of junk on my rifle (except for the expense!), part of me says, any shmoe can shoot with optics, or this and that. But, it's a rare shooter who can be extremely proficient with battle sights at 100 yds, or on-the-move. That's the shooter I aspire to be.

But, like I said, I would like to put together a nice long-range upper, I just don't think I'll have as much fun with it as I do my stock, non-floated version. Time will tell. Thanks, all!

Quoted: I think your right, FF is great for snipers or compittion shooters, but I think it is probably lost on m-4 style rifles. someone correct me if I'm wrong please.

What do you know about black rifles?  I though all you carried was your big revolver with the sandlewood grips

"But, like I said, I would like to put together a nice long-range upper, I just don't think I'll have as much fun with it as I do my stock, non-floated version. Time will tell. Thanks, all!"

There's a solution to this: build both, and find out for yourself!

Afterall, it's a GOOD reason/excuse to build two instead of one!

What do you know about black rifles? I though all you carried was your big revolver with the sandlewood grips

Quoted: But, it's a rare shooter who can be extremely proficient with battle sights at 100 yds, or on-the-move. That's the shooter I aspire to be.

I also believe that a shooter should master irons first and become proficient with them before moving on to optics.  With that being said do not discount the very real advantage that optics give you.

1. Ability to use them in lighting conditionswhere you would be unable to see the irons.
2. Red dot sights are faster to aquire and track.
3. Parallax, red dot sights a more forgiving when you can't attain a perfect "gun range" mount.

These advantages will give you an edge when the SHTF and your targets are moving around and shooting at you in a lowlight environment.

When I had my DPMS built, I asked for a heavy barrel and a FF tube. I learned to shoot with a bolt and I really do not like pencil barrels. I wanted a rifle that can outshoot me in any situation and that is what I have. I did not lower my expectations for weight or "maybe I won't need to hit a bee at 100 yards". It is front heavy and it can shoot better than I can all day.

Quoted: part of me says, any shmoe can shoot with optics, or this and that. But, it's a rare shooter who can be extremely proficient with battle sights at 100 yds, or on-the-move. That's the shooter I aspire to be.

That's kind of a silly logic.  I suppose you'd also like to race a pinto at Talledega?  Shoot pool against Minesota Fats with a house cue? Head to a Dunk-off with Michael Jordan wearing Chuck Taylors?  Bat against Nolan Ryan with a broomstick?

While the arrow does not make the indian, a smart indian knows that to win you choose the best arrow you can.

Quoted: Quoted: part of me says, any shmoe can shoot with optics, or this and that. But, it's a rare shooter who can be extremely proficient with battle sights at 100 yds, or on-the-move. That's the shooter I aspire to be. That's kind of a silly logic.  I suppose you'd also like to race a pinto at Talledega?  Shoot pool against Minesota Fats with a house cue? Head to a Dunk-off with Michael Jordan wearing Chuck Taylors?  Bat against Nolan Ryan with a broomstick? While the arrow does not make the indian, a smart indian knows that to win you choose the best arrow you can.

Bingo. I'm not Michael Schumacher, but me in a Ferrari that could out drive me will still be much faster than me in a Crown Victoria, which I can easily out drive.

I like to shoot my deer in the neck or head, so 1 moa is needed, FF helps keep it under 1 moa.  

One word:    
HEAT

Don't forget the difference in the amount of heat that transfers into the rail system and your hand!  I noticed this the very first time I took my rifle (w/free-floating RASII) out to the range.  I expected that because it was made of aluminum it would get much hotter to the touch than with standard guards.  To my suprize, the section nearest the FSB was warm, but less than 1/8th of an inch away the handguard cap was BRANDING IRON hot.  This heat would have transferred BIG TIME to any metal 4rail non-FF system, but without the metal to metal conduction, it simply couldn't get there.  The radiant heat and heat from convection (hot air) simply will not have the quick scalding transfer power of a metal to metal interface that you'll provide with your non-FF metal rail system.

Besides, the price difference is not much, so why not?

Tex78

Though, I really like the Larue FF railed forends, I still keep thinking about the KISS principle.  The non floating handguards are part of the unique modularity of the AR system.  The shooter can dismantle it should the need arise, and it just seems to me the FF railed forends are a step away from simple convenience.  FF tubes make things more complicated, in that an armorer is needed for installation as in removal of front sight base etc.  I am leaning towards the KAC M4 non floated handguards simply because of user friendly field disassembly........but if I change my mind it will be the FF Larue offering.  

Quoted: Though, I really like the Larue FF railed forends, I still keep thinking about the KISS principle.  The non floating handguards are part of the unique modularity of the AR system.  The shooter can dismantle it should the need arise, and it just seems to me the FF railed forends are a step away from simple convenience.  FF tubes make things more complicated, in that an armorer is needed for installation as in removal of front sight base etc.  I am leaning towards the KAC M4 non floated handguards simply because of user friendly field disassembly........but if I change my mind it will be the FF Larue offering.

Troy MRF buddy, Troy MRF.  Best of all worlds.

Quoted: Quoted: part of me says, any shmoe can shoot with optics, or this and that. But, it's a rare shooter who can be extremely proficient with battle sights at 100 yds, or on-the-move. That's the shooter I aspire to be. That's kind of a silly logic.  I suppose you'd also like to race a pinto at Talledega?  Shoot pool against Minesota Fats with a house cue? Head to a Dunk-off with Michael Jordan wearing Chuck Taylors?  Bat against Nolan Ryan with a broomstick? While the arrow does not make the indian, a smart indian knows that to win you choose the best arrow you can.

I don't think it's silly logic at all. When all your fancy-schmancy gizmos fail, you're left with what? --good old iron battle sights. All I'm saying is, if you're not proficient in the basics (and don't constantly re-train yourself along the way), you're going to be out in the cold if the cause ever arises that you need them --really NEED them. But, then, we're probably off topic now.