Does free-floating REALLY net better accuracy?

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So there seem to be two questions you are asking. The one in the title of the post about free float barrels and the one in the post about pressure on the hand guard changing your point of aim.

For the first question I think that what free floating does is give you consistent harmonics from shot to shot. This will allow for a theoretically improvement in consistent point of impact. Leading to tighter groups. But this is only one factor in consistency so it will not always give you the desired results.

The second question about pressure on the hand guard changing the point of aim seems unlikely in standard shooting scenarios. There just is not enough force placed on a quality hand guard to shift the point of aim. If you hand guard does flex that much then I would look at a different hand guard.
 
Most (not all, but most) people interested in real accuracy these days are mounting optics. And they're putting them on receivers/uppers. Flip-up sights are as a backup for when the optic gets smashed.

I have shot very acceptable groups with irons, all the way out to 600 yards, but, you need a large, contrasting aiming point. Plenty of daylight does not hurt either.

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the guy who did this at 100 yards is a former 1000 yard Wimbleton Cup winner

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The 223 shooter who crossfired from six feet over, is not.
 
I have shot very acceptable groups with irons, all the way out to 600 yards, but, you need a large, contrasting aiming point.

Yes, there are definitely a small minority of shooters who are interested in, and then become capable of, shooting small groups with irons. I am always impressed by it, even if it's not something I want to invest time and money into learning for myself. I have a lot of respect for that skillset. But I suspect few of those people are using folding sights! I could be wrong, but that's my guess.

Outside of that relatively small segment of the shooting world, people who talk about the accuracy benefits of a floating fore-end are planning to reap those accuracy benefits via a scope mounted on the receiver. Flip-up sights are some kind of fall-back/failover device for when your mall security detail is overrun and mortar fire has smashed your optic and you're in CQB next to the Orange Julius stand or whatever. They're not for shooting small groups at long distances.
 
So, that's actually kinda a confusing question.

A free floated handguard/barrel prevents the pressure on the handguard from disturbing the barrel, as stated above. this leads to improved mechanical accuracy of the system.

You could in theory apply enough force to the handguard to noticeably move the poi, due to a change in front sight position relative to the barrel, but you'd probably have to try pretty hard.
I don't think ...well....maybe a few of us are good enough shots to notice a poi change based on pressure applied to a decent handguard.
If you vary your hold that much, I question your accuracy in the first place.
If I'm shooting irons, I wouldn't notice an inch difference anyway.
 
You could in theory apply enough force to the handguard to noticeably move the poi, due to a change in front sight position relative to the barrel, but you'd probably have to try pretty hard.
I don't think ...well....maybe a few of us are good enough shots to notice a poi change based on pressure applied to a decent handguard.

There just is not enough force placed on a quality hand guard to shift the point of aim. If you hand guard does flex that much then I would look at a different hand guard.


Lot of posts in this thread seem to indicate pressure applied to foreend won’t cause shift in POA. That is not my experience.
Most high power shooters I know exert a LOT of pressure with the sling. Enough that they need a very thick glove to keep from hurting their hand.

Steel deflects more than most people think. But most of the deflection is going to come from the aluminum receiver.
Ten years ago there were some YouTube videos where a guy did an experiment showing the deflection in the aluminum receiver With and without carry handle. Maybe someone can find them.
 
Lot of posts in this thread seem to indicate pressure applied to foreend won’t cause shift in POA. That is not my experience.
Most high power shooters I know exert a LOT of pressure with the sling. Enough that they need a very thick glove to keep from hurting their hand.

I think about that a lot in terms of how I shoot out of a jacket vs. in.

In Service Rifle, until recent years, we were (at least half of the time) stuck without free float handguards. I know my own POI’s shifted a lot more with true clamshells than they did with a Rock River float tube though. I assume, or rather would bet, I was flexing the receiver and handguard far more in the floating rifles, but the shift wasn’t as pronounced.

Admittedly though, a free floating A2 guard is still a different set up than the rail mounted, flip up sights we’re discussing here, however. The “fAke2” handguards didn’t hold the sight, so they could flex a long ways under sling tension without really changing the relativism between front and rear sights. Naturally, the true clams were applying all of that flexion to the barrel, directly affecting the front sight. I shoot some flip up sights, but largely, I have little use for them. I can’t see worth a damn any more (already), so I’d rather carry a zeroed QD RDS as a back up, or just head home in the event of an optic failure, rather than mess with irons. I’m sure I can flex most of my handguards enough to influence sight position if I sling up, but usually, I very lightly sling (compared to SR), and shoot from a monopod.

We definitely can bend our rifles, and that can affect our sights, but there’s not a lot we can do about that. However, we do own control, when application rules allow, over our influences directly to the barrel.
 
But I suspect few of those people are using folding sights! I could be wrong, but that's my guess.

Correct. 100 yds. prone w/sling, free floated, front & rear aperture, no folding sights here:
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Not exactly free floated but careful attention paid to all the handguards to stabilize barrel harmonics & make the Garands shoot.
Regards,
hps
 
Correct. 100 yds. prone w/sling, free floated, front & rear aperture, no folding sights here:
View attachment 865986View attachment 865987

View attachment 865988
Not exactly free floated but careful attention paid to all the handguards to stabilize barrel harmonics & make the Garands shoot.
Regards,
hps

Very good shooting!

I have a few of the articles which the Army experimented with various technics to make an accurate Garand. It was surprising to see just how bad service rifle barrels were, even when selected with an air gauge. I forget why the downward pressure at the upper ferrule was chosen, but it was. Of course, as you probably know, the gas cylinder was firmly attached to the barrel, there were arguments about how much clearance the ring should have, but there was no debate that the gas cylinder front had to be fixed in place. And then, the upper handguard was glued into upper ferrule.

Something that ought to be addressed, and it deals with barrel harmonics and vibration, matched out Garand's and M1a's are their most accurate within a limited ranges of bullet velocities. And I am certain this is due to how the hard mounted gas cylinders and barrels vibrate. A free floated AR15 barrel was not as sensitive, though, all of my rounds were as maximum as the primer pockets would allow!
 
Your floating forend really shouldn't be flexing much. If it is, there should be some way to stabilize it or reduce its movement. I agree with the above information, but suggest that your forend be tightened or reinforced to minimize movement.

Yeah I was just thinking the same thing. I was actually kind of confused by this thread. My floating (forend) is rock solid and if it was flexing and bouncy it would be an issue for me. Is forend flex a common issue?
 
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My floating friend is rock solid

You’d flex it shooting with a sling, as done in Service Rifle. It’s just a thin walled tube screwed to a thicker aluminum tube with a steel nut. All of them flex a little when under load, and as @taliv mentioned, even if the tube didn’t flex, the receiver will.

It’s ok, millions of AR’s have had the same aspect for decades, and people still shoot well with them. But ALL tubes flex. Just a matter of managing how much and how much you let it influence your shots.
 
. It was surprising to see just how bad service rifle barrels were, even when selected with an air gauge. I forget why the downward pressure at the upper ferrule was chosen, but it was. Of course, as you probably know, the gas cylinder was firmly attached to the barrel, there were arguments about how much clearance the ring should have, but there was no debate that the gas cylinder front had to be fixed in place. And then, the upper handguard was glued into upper ferrule.

Something that ought to be addressed, and it deals with barrel harmonics and vibration, matched out Garand's and M1a's are their most accurate within a limited ranges of bullet velocities. And I am certain this is due to how the hard mounted gas cylinders and barrels vibrate.

I was very lucky with my DCM Garand purchased in the late 80's for $98 IIRC before they had the different grades. Barrel looked new and, in fact when I recently got a bore scope, it rivals some very expensive match barrels I've seen. I accurized it myself as follows.

First glass bedded the action. Front hand guard was screwed and glued to rear band and rear guard was also glued to rear band. Removed enough wood on rear hand guard to insure it would not touch front of receiver when things heat up. I was fortunate that my gas cylinder fit barrel splines tight enough I didn't have to peen or center punch barrel and I found a gas cylinder lock that tightened up at right position. Reamed the rear ring on gas cylinder to provide a few thousandths clearance between cylinder and barrel, also made sure to have clearance between cylinder and front of front hand guard to allow expansion room as barrel heated. Never had a problem w/vented gas cylinder lock screw, but replaced mine w/the older solid plug. Worked over the trigger to a clean 4.5# break. Added NM sights and took it to the matches as long as I was able to see the iron sights.

A few years ago I started the quest to put an optic on the old girl to get it out of the safe again. Not wanting to drill any holes, designed a base to replace rear sight and two optics later wound up w/the Primary Arms 3x compact. Not much to look at but shoots great.
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The 125 gr. NBT's are a bit faster than M2 Ball or M73 Match but didn't seem to hurt accuracy any.

The base mounting screws use rear sight elevation spindle holes in receiver ears; remove these two screws and replace rear sight to restore rifle to original configuration.

ETA: As Slamfire said, it is very important that gas cylinder doesn't move around any as there is a lot of activity w/op rod slamming back and forth close to tip of barrel. My son was not quite as lucky as I. His DCM Ml had good barrel but gas cylinder/barrel fit was a bit sloppy. I hate to peen a barrel, so tried something different when I accurized his rifle. Drilled and tapped a small hole in the cylinder under the front sight and used a small allen screw to pull cylinder up tight against the two lower barrel splines. Worked like a charm; rifle shoots great but I pity the poor gas gun plumber that tries to remove the cylinder after I'm gone.

Regards,
hps
 
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My experience is more with bolt guns than AR's, but I'd believe the principles are the same. The key is CONSISTENT pressure on the barrel. There are some very well respected custom rifle builders who full length bed their rifles. Melvin Forbes who runs New Ultra Light Arms Firearms full length beds his rifles and they are known as very accurate hunting rifles.

On the other hand most gunsmiths go with free floated barrels. I believe either method can result in very accurate rifles, IF DONE RIGHT. But it is easier, and less expensive to get it done right going with a free floated barrel. Thinner, hunting weight rifles often respond better to full length bedding than heavier target barrels. You usually see the heavier barrels free floated.

The stock matters too. Having the barrel contact a synthetic stock is much less of an issue than a wood stock. On a wood stock I'd want a generous free float since the wood will naturally expand and contract as atmospheric conditions and altitude change. Synthetic does not do that.
 
my personal experience with this matter,

I built a 450 bushmaster AR that utilized a 15" hand guard that came with a "end cap" of sorts that fit inside the muzzle end of the hand guard, I am assuming to keep debris from entering inside of it. I installed this little end cap as I saw no reason not to initially, the ID of the end cap was just large enough for the barrel to fit through with little room to play with. After the rifle was complete and I started to shoot for groups, the groups were awful and I was very displeased. It didn't take long to notice that the barrel was contacting the "end cap" and leaving a mark. 4 screws later and the end cap was removed, nothing else was changed, went back out to the bench and my groups were cut from 3-4" at 50 yards to 1.5" at 100 yards. To me that is a dramatic increase from just barrel harmonics, much more than what I would imagine the flex of a decent handguard would discount.
 
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