To float or not to float

[Bart B.]

coyota1, nobody shoots 1 MOA groups offhand; at any range. But a good shot can shoot 10 MOA offhand and tell if their rifle will shoot 1 MOA (or better) groups at 100 yards; often at 200 yards, too.

[Bart B.]

wpsdlrg, top level competitors have been free floating barrels in stocks with the receiver section factory routed without a perfect fit decades before epoxy bedding was even experimented with. How else did high power match rifles shoot 1 MOA at 600 yards with arsenal match ammo in the 1920's and 1930's; no epoxy bedding was around back then. They's shoot inside 1/3 MOA at 100 yards so built.

Remington's 40X centerfire match rifle stocks were factory routed then the barreled action bolted in and the barrel was free floating from the get go. They didn't ship unless they shot 1/4 MOA at 100 yards. Even the first benchrest rifles' receivers in wood stocks with the barrel free floated as the receiver was "lamp blacked" to a perfect fit shot 1/4 MOA at 100 yards.

Anschutz .22 rimfire Olympic rifles had their barreled actions dropped into factory routed stocks without any special fitting whatsoever other than a steel bar to locate the front to back position of the receiver in the stock and serve as a recoil shoulder. The barrel was free floating in the fore end. They won gold medals and set records without any epoxy bedding.

Since the 1950's when epoxy bedding first came about, the most accurate rifles have had the fore end barrel channel relieved for clearance then O rings or tape wrapped around the barrel to position it clear of the channel all the way around while the receiver set in a puddle of epoxy about 1/10th inch thick around it. So, both bedding and barrel free floating was done all in the same step.

[coyota1]

Bart B, I know that free floating a good barrel is the way to go. My sporter barrels probably are not the quality of heavy match barrels, and react unevenly to heat. Now even off hand shooting I m holding the forend in place of a benchrest sandbag, or rest. I have made many accurate off hand kills with my rifles that are fully bedded, and my POI stays the same.

[reynolds357]

Bart 95% or the rifles I have ever had I free floated if they did not arrive that way. The two mentioned above that were full length bedded did maintain zero from the only two positions I ever shoot them from. I will also add they were both synthetic stocks. Those being rest under the front foreend and my hand on the front fore end. I dont use the sling to shoot while hunting. I find me a small tree and pull the stock firm against it. I 100% agree with you that free floating is the way to go in most circumstances, but these particular two crappy barrels did not like it too well.

[Bart B.]

One thing to consider is, if an epoxy bedded receiver with the barrel free floating doesn't shoot as accurate as with the barrel bedded, there's something wrong with the receiver bedding or how it's held to the stock that's the problem. There are more wrong ways to epoxy bed and fit a receiver than right ways.

[reynolds357]

This whole thread got me to thinking. I asked a custom rifle builder I know about full length bedding due to a problem I am having with another rifle. He said in theory it does not work, but pretty regularly he has to bed pressure points into the light weight rifles he builds to make them shoot. I was looking at one company's bedding instruction and they said to free float while bedding but keep in mind that you may have to go back and bed a pressure point to achieve desired accuracy. I dont know why it works, but on some thin barreled rifles, full length bedding or bedding an intentional pressure point works.

[reynolds357]

I found this quote from Gale Mcmillan in another thread on here.
"Posted: 01-08-2000 07:08 PM
Quality barrels will perform better free floated but poor quality barrel will perform better with a 3 to 5 lb fore end pressure. The reason for this is that
poor quality production barrels are not stress relieved and will tend to walk as it heats up. By putting fore end pressure you are actually bending the
barrel upward in an ark so that as the bullet starts down the bore it is trying to straighten out the gentle bow induced by fore end pressure and it holds
the barrel against that force. This causes the bullet to exit at the same vibration point shot to shot even though there may be a velocity spread. It is best
to bed the rifle with free floated barrel as it is easy to bed the barrel with fore end pressure should it not shoot free floated. Just hold the stock in a
vice and hang a 5 lb weight to the front swivel and put bedding material in place in the fore end tip and let set up. This means that free floating is not a
panacea and does not always help. Some do and some don't This is why all factory barrels are generally bedded with fore end pressure."

[coyota1]

This is why all factory barrels are generally bedded with fore end pressure."

This is the way my 700 vls came. The stock came with a pressure point in the stock.

[Bart B.]

Gale McMillian's often quoted theory:

By putting fore end pressure you are actually bending the barrel upward in an ark so that as the bullet starts down the bore it is trying to straighten out the gentle bow induced by fore end pressure and it holds the barrel against that force. This causes the bullet to exit at the same vibration point shot to shot even though there may be a velocity spread.

That's an easy myth to shoot holes through.

First off, there's no guarantee that a poor quality, non-stress reliefed barrel will always bend in the vertical axis when it heats up. Nor is the direction always going to be either up or down; it will be in the direction the stresses bend it.

Second, any fore arm pressure on the barrel will change with how the rifle's held by the shooter. From a fixed amount and axis when the rifle shot offhand where it's constant from shot to shot to any position that [puts pressure on the fore end changing the force axis and direction. That'll change how the barrel wiggles while the bullet goes through it and the bullet will exit at different directions depending on that external force and its axis.

Third, bullets leaving at different muzzle velocities exit the barrel at different angles. The bore axis at the muzzle's going through a narrow range of angles all the time as soon as it's fired. And the barrel will wiggle and whip at the same frequency for every shot fired regardless of how long it takes for the bullet to go from case neck to out the muzzle and from very cold to very hot. Adding a variable pressure to any point on the barrel will change the direction and amplitude the muzzle axis wiggles at but its frequencies will stay the same.

Gale McMillian claimed the Rem 700 box magazine recevers are stiffer than the Win 70 ones. People have bet him thousands to prove it but he never accepted the challenge. Folks who've measured how much each receiver bends from a given force know which one's stiffest.

[coyota1]

Bart B, why did Remington make the VLS with a pressure point in their laminated stock??

[reynolds357]

Bart, Gale was a legendary rifle builder. The man built many world record holding rifles. He might not be right about everything, but I know pressure points make some rifles shoot better. I cant tell you why, but I know it does. A tupperware stock and a $1200 stock seem to follow a different set of rules. Some stocks have so much flex in them it really does not matter how well you bed them you are not going to realize the results of a good bedding job. Now that I really think it through, both rifles I full length bedded with great results were rifles with junk stocks. One of them was Savage's stock with those stupid plastic molded pillars. The other was a Remington mountain rifle with a composite stock that is the softest, most flexible stock I have ever seen in my life. Both liked full length bedding. Why? Don't know, but it worked.

[Bart B.]

Ask Remington why they put a pressure point in their stock; fore end I assume. I have no idea what their reason was/is. May well have been the same reason they put adjustable pressure points in their original 40X match rifles at their stock's front end at 45 degrees to the barrel but that was a disaster and smart folks backed those adustments out all the way totally free floating the barrels and they shot more accurate.

It doesn't matter how much flex there is in a stock; barrel either for that matter. As long as it's repeatable for every shot, that's all that's important for accuracy. More often than not, that pressure point in the fore end tends to counteract a poor receiver fit to the stock and rifles do sometimes shoot better that way. It's cheaper than epoxy bedding the receiver, but not as good accuracy wise.

[reynolds357]

In my mind, the problem with flex is that nothing is going to be repeatable. We both agree that a quality stock, quality action, and quality barrell; are at their best free floated. Lesser quality components seem to follow their own set of rules at times.

[Revolver1]

Free Floating a barrel is vital on any rifle. No need for bedding if barrel is floated properly to the forcing cone.

[reynolds357]

Revolver, I will remember that the next time I am wasting time and money bedding my 1000 yard rifles. You sure you are not talking about a shot gun?

[coyota1]

Revolver, I will remember that the next time I am wasting time and money bedding my 1000 yard rifles.

Same here.

[Bart B.]

reynolds357, if everything's not repeatable, the bullets won't even come close to landing at the same spot. Accuracy's the reduction of all variables to zero; or as close to zero as possible.

[reynolds357]

Bart, did you not pick up the the sarcasm dripping in my post?

[603Country]

I hate to intrude on a good hair-pulling fight, but I'm with BartB. I'll say it my way, but I do believe that the fewer variables you have that are impacting barrel whip (flex, harmonics, call it what you will), the better your rifle will or can shoot. Barrel pressure points in the stock of consumer firearms are there for a purpose, but I think that purpose is to reduce or dampen accuracy problems that arise from other parts of the stock. Note that I say "consumer firearms".

Regardless of how thin the barrel is, the harmonics should be repeatable if you have good match type ammo and a properly stocked and bedded action. Repeatable harmonics should allow good accuracy. The thinner the barrel, the more that barrel quality should matter. If you have a thin and lower grade barrel or one of those cheap synthetic stocks, you will need that pressure point in the stock.

I have a Ruger 77 Compact with that short thin barrel, and it seems to like the pressure point. It shoots quite well, so I just leave it alone. If I start messing with the stock, I'll want a new high quality stock and I might as well get a great barrel while I'm at it. I just can't make myself get started on that project when the rifle is so good as-is. It's the only non-floated rifle that I have. If I need to shoot a pig at 400 yards, the rifle is fine. If I need to shoot a pig in the left eye at 400, I'll go get the Swift with the aftermarket barrel and tuneup.

[Bart B.]

603country, all you've said above is true. . .except for one thing.

Barrel weight, or how thin it is, has nothing to do with accuracy. Each barrel has the same fundamental frequency it wiggles at plus the harmonics that are multiples of the fundamental. With equal bore, groove and chamber dimensional quality they'll bot shoot with the same level of accuracy. In other words, barrel weight, thick or thin, has nothing to do with accuracy. Period.

[603Country]

BartB, you missed my exact statement on the barrel. I said "if you have a thin AND lower grade barrel". I do believe that a thin barrel of good quality will do just as you say. However, a thin and less-than-good barrel might go a little serpentine on you when it gets hot. Not every barrel is a great barrel. I think that if a fellow wants an ultralight rifle with a real thin barrel, he should get top notch quality. I sure would. But, as I've said, I have that Ruger Compact with the short thin barrel and pressure point or points. I'm not messing with that one. It ain't broke...so...

[Bart B.]

603, all barrels do a "little serpentine" when fired. That's caused by the harmonic frequencies above its resonant/fundamental one. Their quality has nothing to do with that. It's basic vibration issues well understood by mechanical engineers who use formulas to calculate it for all sorts of reasons; earthquake proofing structures and other things such as smoke stacks (a really big barrel in effect) that's held rigid at one end and free at the other. Check out Modes 1 through 3 in the following and note the serpentine in 3:

http://www.varmintal.com/amode.htm

I don't think I missed your exact statement, but the way it was worded was why I commented as such. If I did then, OK.

[603Country]

Let me try again. Not all barrels are great barrels. At a theoretical level, a heavy barrel and a thin barrel may be equally accurate. At the consumer level however, I do believe that the accuracy of a thin barrel is impacted more by barrel quality and quality of the bedding of the rifle. In other words, a standard or heavy barreled rifle with mediocre stock bedding will mask the negative effects of the bedding better than a thin barreled rifle will. That's why I said, and why I believe, that if you want an ultralight rifle you really want a high quality barrel. And, high quality bedding.

As for the original point of this thread - to float or not - I do believe that floated is the way to go, if the rifle is bedded well. Again...back to my Ruger Compact with the short thin barrel. I wanted the barrel floated and I had an extra short-action synthetic Ruger stock (came with my standard barrel Hawkeye). I dropped the action into that synthetic stock and it was instantly floated, but the rifle just didn't shoot worth a darn. Like I've done before with other rifles, I put a lot of reloads through it and tinkered with loads for days and days, trying to find the elusive great load. I couldn't do it. Hmmm, maybe it's the darn stock, since the Hawkeye didn't shoot that great in that same stock. So I put the action back into the original wood stock with barrel pressure points and it shoots great. I have absolutely no doubt that the rifle will shoot at its best in a high dollar well-bedded stock, but that's a lot of money to spend just to shrink the groups by 1/4 of an inch, so I'll leave it as is for now.

And...I do have that short action synthetic Ruger stock for anyone that wants it.