Questions about barrels

[Nube]

OK I have used the search and come up with nothing.

1. How hot does a barrel have to get to affect accuracy (In General Terms)?

2. I saw a video on the net about switching barrels and it made me curious about that. Can you switch a light barrel for a heavy barrel in the same action (assuming the stock will or is made to fit)?

Number two might be better in the Smithy?? IDK Thought rather than clutter I'd combine them as there are knowledgeable people all over the board.

Thanks for the replies in advance, all are appreciated!

[Art Eatman]

A quality barrel, if free-floated, will commonly continue to shoot small groups. Other issues, such as fouling, can affect group size with a very long string of shots.

A good machinist should have no difficulty in such a barrel change. The critical point is that of headspace.

[jmr40]

There is no simple answer. Generally speaking a heavier barrel will take longer to heat up. But also longer to cool down. How hot it needs to be to effect accuracy is debatable. As near as I can determine the quality of the barrel plays an important role.

I've never spent the money for a quality aftermarket barrel, but there are people who claim that a well made barrel can be pretty hot and still deliver good accuracy. In my experience the really thin factory barrels like those seen on the Remington MT Rifle are pretty accurate for about 3 shots, then they start throwing bullet all over the target. On a standard sporter weight factory barrel I can get in multiple shots with no decrease in accuracy.

Changing the barrel is an option on MOST rifles. Some of the budget rifles can't easily be changed, and on others the cost of changing the barrel exceeds the cost of the rifle and isn't considered a wise move.

On most rifles this is the job for a gunsmith, but it can be a DIY project with Savage rifles with a few basic tools.

[RC20]

Pretty much as jmr40 says.

Any action can take a heavy barrel to at least as large as the receiver ring. Mine are all stock Savage actions with 1 inch barrels with no taper (Bull).

Sako (Finnbear, Vixen) had a reputation for not jumping all over the place and that would have been an early leader in light almost pencil barrels.

Quality and processing of the steel, how the rifling is put in and the follow up stress relief all play a part as well as the original hole through the steel. The family has a 270 that will shoot 3/4 to 7/8 MOA x 5 shot groups. I have not tried to push it further than that.

Hammer forged were not great accurate barrels but CZ stores theirs outside for months or a year and something about the rusting process works toward accuracy (they also do more finish work)

You have 3 types of rifling, Hammer forged (the big guys in bultk, Ruger, Remington etc) button rifled (pulling a rifling shape device through the hole and a twist as it does it) and cut rifled (multiple cuts and or multiple land grove setup)

The first two put major stress on a barrel and needs to be relieved. Savage used the button method as they never got up enough quantity to go forged (pretty costly)

Lot of button rifled machines left from the inter war and WWII years and a bit post.

Button rifled (custom) are the sort of mid level in barrels (Shilen and Criterion would be my two go to but a lot out there)

Cut rifled are the tops, a year lead time and the top bench rest guys have those. Stress free but you have to lap them as they are rougher than the rest shape wise. Lilja - Bartlein would be two of the well known ones.

As for temperature, for David Tubbs it might be an issue, I shoot from around 5 degree on up through 80. I see little if any difference in cold shots to warmer shots. A couple of my custom barrels seem to like a couple of fouling shots, one could care less.

I have not been able to get a Savage pencil barrel to shoot (I had a heavy barrel varmint that was quite good). I did not spend a lot of time on those pencils though.

As for me, I shoot until they start to get hot (if they do on a cold day with cease fires its not a factor) and then switch to another rifle and let them cool. Mine are Bull barrels so they do take a while to cool down.

I would not shoot a Sako into hot, 5 is the limit and let it cool down. I don't know you can mess with it doing that but I have no desire to see it change.

How much that can change if you are a recreation bench rest like I am and David Tubbs who if he does not put them all into one hole at 300 yards goes home crying, I don't know.

I do know that getting under 3/4 MOA is not hard, under half is tougher. Under 1/4 is another bugger of getting deeper into the weeds of minutia.

[RC20]

I will add that Savage setup is not just the nut but fine threads you did not see back in the the day.

Remington also has fine threads but does not use a nut. Once the original factory barrels is removed from a Remington, you can get what they call a Remage which does have the nut thread cut up the outside and you can do the same thing with a Rem as you can a Savage after that (do it yourself)

I have done it 8 times or so now. About $125 in tools and you are gun smith free and proud.

1/2 MOA and under is doable with that setup.

Savage has one advantage still, its god a floating bolt head. Its another small step in not having to blueprinting a receiver. Self aligns.

I am getting under 1/2 MOA consistency, this weekend I shot a couple of 10 shot groups in an 06 Bull at 3/8 MOA.

The barrel plays a bit part, but the shooter and the receiver and the ammo also play roles and all have to be better than the gun is capable of to get consistency.

I don't have an delusions of being Dale Tubbs. I am tickled I can do 10 shot groups now as when I started I was happy with a good 3 shot group.

And none of what I do applies to hunting, other than cartridges and center fire rifles, they have not a lot to do with each other other than incidentally .

Good 5 shot groups and 10 shot groups are there to tell you its not an accident. With a 10 shot group that is good, your gun is good, you are pretty decent and your ammo is pretty good.

I do have days when I have a very good 4 shot and then the flyer that I know is not me.
I suspect my ammunition prep has a hole (which I am working on)

One guy wrote if he had a bad shot that he knew he had done good with he pulled that case and pitched it. There may be something to it and I am thinking about it as well.

[Jim Watson]

1. A target shooter is going to demand a quality barrel bored, reamed, rifled, and contoured straight; fitted straight and square to the action so as to not wander as it heats up. He will likely be shooting fast and cannot tolerate loss of accuracy with barrel temperature. Factory barrels are not made so carefully and may be limited on the number of good shots before a cooldown.

2. The easy route to a switch barrel rifle is a barrel nut installation like Savage. Careful headspacing on the initial installation and a witness mark will get you back to where you started.
There are benchrest rifles made with conventional shoulders but with the barrels not turned in as tight as a hunting rifle. Short handled wrenches will make the change. This allows them to shoot more than one event with the same action and stock.
There are foreign exotic designs with true quick change barrels, if you care to pay for them.

[std7mag]

I have/ have had, factory "pencil" barrels shoot 1/2-3/4 MOA for a 5 shot group.
With my limited budget, i cannot usually afford a rifle for hunting and a rifle for competitions. (My wife's Savage 110FP being the exemption)
Hence my rifles primary purpose is for hunting. My prefered manufacturers are Savage and Ruger. By no means am i bashing another manufacturer! They all make some outstanding rifles! And have historically had some issues.

I did join membership in a range that allows you to shoot to 1,000 yards. Part of the requirements for membership is that you must shoot in at least 1 match per year, to show safe handling of a firearm.
My first year, and first ever match, was shot with a fairly stock Stevens 200 in 7mm-08AI. ( i did the chamber reaming and headspace myself).
Let me tell you, there was no way in heck you were putting your hand near, much less on that barrel!!

Now i have re-barreled 2 rifles. That same Stevens 200 is now a 250 Savage, and a commercial Mauser is now a 284 Win. Both hold sub MOA with hunting bullets. Both are E.R. Shaw barrels. I chose them due to 2 factors.
1) They fit my limited budget.
2) E.R. Shaw is a local to me manufacturer.

I've been looking at other barrels that i would love to try. Pac-Nor with their polygonal rifling ($400 ish dollars) , and Proof Research carbon wrapped ($872 chambered, ($400 ish blank).
My E.R. Shaw by contrast was $272 delivered to my door.
Are they competition barrels? No! But they are decent, affordable barrels that can be put on by someone at home without thousands of dollars of equipment.

Proof Research has a video on Youtube on how tough their barrels are. Barrel was hand tightened onto the action. Shot 3 shot group. Hand screwed off. Smacked repeatedly against a cinderblock, hand screwed on, and shot 3 tomes again for no change in point of impact.

[Nube]

Wow it seems the more I know the less I know. Thanks for the replies so far!

[RC20]

Happy to do so. Its a darned interesting world.

My take was that I was going to get the best barrels I could (and scopes to go with them) - building the guns up was maybe $800. My highest cost scope is $1200. Oddly while its good (dot type) its light gathering is subject to a lot of variation on cloudy days (more often than not) annoy9ng but can adjust it and does well.

Easiest for all use was a Cabella Alaska Guide discontinued in 24X I got for under $200. Got figure.

[ndking1126]

I'll try to find the article, but someone did a study that determined the temp of a barrel affects pressure more than the temp of the cartridge. What this means is if you have an accurate hunting load in the winter, it may not be accurate in the summer (or vice versa). Higher temps cause higher pressure, which causes more velocity. The increased (or decreased) pressure may add (remove) enough velocity that the ammo doesnt shoot as accurately. That gets into accuracy nodes, optimal charge weight vs 10 round ladder test, etc.

I think the easy answer is go shoot your rifle and see when groups open up. That and as a general rule if your barrel is to hot to touch it's too hot to shoot.

Edit: here is a post I started. https://thefiringline.com/forums/sho...d.php?t=600100

Go to post 6 for a link to the study I was referring to.

[Art Eatman]

To add to the complexity, I have read that some powders are sensitive to ambient temperatures, giving different pressures from a freezing winter temperature to a hot summer day. (This is from reading, not from experience.)

[RC20]

All powders are affected by temperature and the velocity shifts form cold to hot or hot to cold.

Newer ones reduce that but not eliminate it.

[LineStretcher]

I'll take the complexity out of it.

Q. When will a barrels temperature affect accuracy? A. The moment you notice it affecting accuracy.

Q. Can your switch to a heavier barrel with the same action?
A. Yes.

Let me briefly explain. You can never reliably know when the temp of a barrel will affect accuracy. A heavier barrel such as a bull barrel is not there to fend off heat, it's there to improve accuracy because it is less affected by the combined harmonics of the stock and rifle. The increased surface area does help to cool it faster and if it's fluted then you have even more surface area.

As for the switch, you can put a 3" diameter barrel on an action if you want. The threading, chambering, final reaming (setting head space) all remain the same. Stock fitting is a given but usually only involves the barrel channel which is a fairly simple job.

[Erno86]

When shooting 3 shot groups...you'll want to shoot fairly rapidly before the receiver heats up. Once the receiver heats up, accuracy will deteriorate.

To prevent premature throat erosion cracks in the bore...try not to get the barrel get at or past the 180 degree fahrenheit mark (which is enough to fry an egg or when the barrel feels too hot to touch).

You can purchase paper temperature strips, that you stick on the side of the barrel. But I find that oil on the barrel, can cause the glue on the strips being made worthless.

Nevertheless...temperature strips will teach you what the 180 degree mark feels like on your fingers.

[handlerer2]

I shoot very high powered rifles in all seasons. 300&340WBY, and 6.5x284.

I read about and now use isopropyl alcohol to cool the barrel and receiver.

I use a rag soaked with the alcohol to cool the barrel from the outside and a bore mop or patches to cool from the inside. I was skeptical about this, but it really works. Alcohol will cool much faster than water and it will not cause rust.

The WBY rifles heat up very fast and get very hot. I like to test 2 or 3 handloads every session. In the summer when it's in the 90's this speeds things up considerably. It may even extend the life of a barrel, if it never gets as hot as it otherwise might.

I am not concerned about the fumes as I shoot outdoors.

[Erno86]

If you put the rifle in the rifle rack that is subject to direct sunlight on the range --- The P.O.I. might be affected because the sun's rays only heat-up one side of the barrel.

[RC20]

A heavier barrel such as a bull barrel is not there to fend off heat, it's there to improve accuracy because it is less affected by the combined harmonics of the stock and rifle. T

And it takes a lot longer for the heavier barrels to cool down.

[RC20]

When shooting 3 shot groups...you'll want to shoot fairly rapidly before the receiver heats up. Once the receiver heats up, accuracy will deteriorate.

That would be wrong. The receiver has nothing to do with the issue and the faster you fire the hotter it gets. Its totally illogical.

[Erno86]

RC20 -

I guess Bart B's (#17 post) can explain it better than I can:

https://thefiringline.com/forums/sho...d.php?t=524604

[std7mag]

Emo,
When shooting competition, i noticed some guys just laying there. Not shooting.
Then, they would pick a time, where they would put rounds down range as fast as the targets were pulled, came back up.
Found out this was due to crosswind, not barrel heat.

Berger changed their target bullets, with a thicker jackets due to tempretures in the chamber.
The original VLD had a thin jacket. They found out at the end of a string of 20 rounds that the core was actually starting to melt, separate from the jacket. Causing fliers towards the end of the string. Typically last 3-4 rounds.

Typically i shoot 1 round, and while waiting on the target, wind call, i pull spent casing, insert fresh round in the receiver but don't close the bolt, till i'm ready to shoot again.
This hopefully allowes time, and air into the barrel/chamber to help with cooling. Or at least overheating.
Also doesn't let the powder and bullet get too hot.

[ndking1126]

Found out this was due to crosswind, not barrel heat.

Zak Smith mentioned on here multiple times that the best length of time to wait between shots was "before the wind changes". Hard to argue with someone like him.

[RC20]

RC20 -

I guess Bart B's (#17 post) can explain it better than I can:

What Bart B is talking about is the barrel pushing against the face (more so if not uniform ) of the receiver, not the receiver heading up.

He then goes on to say even a uniformed face (blue printed) can do that if the barrel is not equal all around and one part when heated up moves more than the rest.

But, if heat is the issue, shooting as fast as you can make MORE heat in 30 seconds not less.

Space out the 3 shots at 1 minute and the barrel cools back down from the last shot.

Any real heat issue would manifest at 5 shots, not 3. Even 3 fast shots does not heat up any barrel much.

3 shots followed by 3 shots of course does.

[precision_shooter]

1. How hot does a barrel have to get to affect accuracy (In General Terms)?

2. I saw a video on the net about switching barrels and it made me curious about that. Can you switch a light barrel for a heavy barrel in the same action (assuming the stock will or is made to fit)?

1. This is going to be very subjective and will vary greatly even on the same make and model of barrel. Things like barrel profile/weight, length, caliber, material, how well it’s fitted in the action and stock, etc and any combination of those will all play a factor in how “hot” the barrel has to get to affect accuracy. Some as little as 3 shots back to back will heat a barrel enough to cause accuracy issues. Others may take 10 or more shots back to back.

2. Switching barrels is only readily possible using a barrel nut (like Savage uses). Very few tools needed and can be accomplished by most competent people at home. Remington style barrels/actions that screw the barrel into the action will require much more tooling and is likely best left to a gunsmith who can turn the barrel so that it can be properly tightened/torqued while giving proper headspace.

[TXAZ]

Start watching at 3 minutes.
If the barrel is glowing cherry red, you're in danger of seriously changing the accuracy.

https://www.youtube.com/watch?v=8CLMbXOBnWE


BUT: Unless you have a really hot rifle (with muzzle velocities > 3,000 fps), it's likely in the high hundreds or thousands.

[BeeShooter]

Some of the older rifles (60s and 70s) have very good barrels. For the most part I've yet to see newer model rifles that have barrels that are close to the quality of Kieger, McGowen, Brux, and the countless other aftermarket barrels.