Free Floating Barrel

[Yamavira]

Hi
Removed the action from my Ruger M77 MK1 in 0.308 and was surprised to find that the forend wood has been bearing very heavily against the underside of the barrel (blueing has been rubbed away & the bottom of forend channel is really bruised).
The rifle is shooting fine & grouping okay.
Question. If I remove the high spot on the forend wood allowing the barrel some "free float" is it likely to upset the harmonics of the barrel & spoil the grouping or is it more likely to improve the grouping because the barrel will not be "jammed" up against the forend halfway along its length.

Appreciate any comments

regards
yamavira.

 

[Red Cent]

"The rifle is shooting fine & grouping okay."

 

[Dr T]

Once you have removed the rifle from the stock, all bets are off. Once you remove the action, the point of impact will shift and you have to sight in again. My Ruger 77s have tended to be quite sensitive to the the tension of the screw holding the stock to the action. If you can replicate the performance when you put the action back in the stock, you are good to go. If not, I would free float.

I personally am inclined to free float barrels (use a dowel rapped in sandpaper and seal with tung oil. As an aside, I am also not inclined to ever remove an action from a stock once the rifle is dialed in without a very good reason).

 

[blackDdefense]

free float it. The harmonics is not something that they would use the stock to improve because the stock is not as strong as the barrel. As Dr T said...remove the high spot and when you are done you should be able to slide a dollar bill all the way down between the barrel and stock clear to the receiver

 

[Vern Humphrey]

If I remove the high spot on the forend wood allowing the barrel some "free float" is it likely to upset the harmonics of the barrel & spoil the grouping or is it more likely to improve the grouping because the barrel will not be "jammed" up against the forend halfway along its length.

If it ain't broke, don't fix it.

 

[JerryM]

I have never found free floating to help accuracy in a light barrel. Pressure has always worked better for me. I like the idea of free floating to prevent changes in POI due to stock warping, but in my sporter weight rifles accuracy has always suffered.

I agree that if it ain't broke, don't fix it.

Jerry

 

[USSR]

If it ain't broke, don't fix it.

+2.

Don

 

[jmr40]

Most rifles shoot better free floated, but many others do much better with forend pressure. Ruger specifically says not to free float their rifles. I've read reports of some who have done so and they felt it improved their accuracy.

I'm in the "If it in't broke, don't try to fix it" camp.

 

[NCsmitty]

Dr T took the words right out of my mouth, and saved me a bunch of keystrokes.

In my experience, I have never had a rifle shoot worse after floating, but usually I also glass bed the action before final assy.
I have not owned a Ruger, but most bolt rifles usually follow a common action to stock fit.



NCsmitty

 

[juk]

When I floated the barrel on my 77 mk1 308, It did not help with accuracy. It DID get rid of a flyer problem I was having. For what it's worth, my Ruger had the factory heavy 24" barrel, not the sporter weight barrel.

 

[LTR shooter]

I would go along with the others and not mess with anything if it shoots well.

In my case I have a Weatherby Vanguard Deluxe .30-06 that does not shoot to my liking and has a great deal of upward tension on the barrel.I am going to float the barrel. If it was shooting consistent I would leave as is.

Some factory sporters like the Tikka T3 Hunter and Savage American Classic have free floating barrels and have a rep for good accuracy.

 

[Art Eatman]

Generalizing, realizing that there is no such thing as "always":

I've almost always had improvements in group size from free-floating and then putting a light-pressure shim at the forearm tip. At most, maybe five pounds of pressure. As near as I can tell, this acts to make for uniform harmonics, shot to shot.

One of those deals, "I know what it does; I don't really know why it does it." My uncle's notion was that it acted as a damper, just like the shock absorber on a car. Whatever; been working for over fifty years, now.

It's rare that I didn't change some sporter from being 1.5 to 2 MOA to being a 3/4-MOA shooter, and occasionally better.

 

[Dr T]

My poster child for floating the barrel of an erratic shooter was a Remington Model 7 7mm-08 (18.5" ultralight barrel with sights) in a factory fiberglass Kelvar stock. The reinforcement pad behind the front sling swivel was bearing on the barrel at about 4 or 5 o'clock causing it to group erratically (that little barrel gets hot in a hurry). Removing this pressure point took it from 2.5" groups to much, much smaller (my best 3 shot group was 0.19" at 100 yards--you can cover it with a dime).

My poster child for NOT floating a barrel is a Ruger Model 77 (pre-Mark 2) in 270 Win. Following some advice, I took the bedding screw to snug and then gave it 3/4 of a turn. It will shoot about 0.75" groups with good handloads.

It's a Hobson's choice, and you have evidence to support leaving things alone.

(While you may think that this is now akin to beating a dead horse, I would point out that Hobson was the owner of a livery stable...Very bad pun, I know).

 

[Red Cent]

If you free float the barrel, go the extra mile and pillar bed the action screws. Pillar bedding the screws can replace the glassing of the action. 'course all would work together. Pillar bed, glass, then free float.

I would venture to say all 1000 yard competition guns and F Class rifle re all pillar bedded.

This guy cheats.Its a single shot.

http://www.6mmbr.com/pillarbedding.html

Pillar bedding will allow you to tighten the action to the stock with constant and somehwat repeatable tightness. You will be tightening metal to metal and doing away with the variable of wood. The materials are relatively cheap and diy helps. Its easy.

 

[Still Shooting]

Early Ruger M77 Accuracy Problems

I bought an early M77 (257 bob) back in the mid-80's, and was pretty frustrated with it: At 100yds First shot - dead on. Second shot - 3-4" high and off right. Third shot - 3-5" off, usually left. I fussed and fretted, and finally discovered that the forend wood was bearing against the barrel about 5" back from the tip. I sanded out the "high spot," and got an immediate change to 1/4 MOA.

Fast forward to 2010: After 5 - 6 years in the rack, the gun was just inside 1/2 MOA. I installed a Timney adjustable trigger, because the factory adjustable was an unreliable, not repeatable, POS. It changed the action bedding, and I ended up having to float the barrel. I then got back close to that magic 1/4 MOA number. Apparently, the stock had "moved" some more over time, and of course, removing wood to fit the Timney altered the action bedding. Now the gun shoots pretty well, but if I set the rest/bag too far forward on the forend, the wood bends and again touches the barrel, changing POA and opening up the group. Current plan is to pillar bed, and experiment with a shim at the muzzle end of the wood.

 

[Bill_Rights]

Art,

When you say

then putting a light-pressure shim at the forearm tip.

what kind of material did you use for the shim? Metal? Wood? Plastic? I think the degree of damping depends upon how stiff this shim material is.

 

[gamestalker]

There are two sides to this coin. First off, it isn't having problems grouping so why risk having to create one. But on the other side, nearly every bolt action I have or have had I floated the barrel and had great results. But I have a thing about tuning my bolt actions right out of the box I float them, button lap the barrels and actions, trigger job or replacement, and bedding them. It's really a matter of how much work you want to do to possibly see little difference in performance. For some, such as myself, it's more of a common practice I consider a part of the hobby.