Cut or Buttoned rifled barrels

[SBP]

Hi 

Just out of interest, what are peoples thoughts between the two rifling methods. I've always been told a cut rifled barrel has the edge over a buttoned one. Have people on here found this to be true or just a myth?

 

 

[Moorlander]

??

[Catch-22]

8 hours ago, Moorlander said:

??

?

[Leeman]

myth.

Richard.

[Re-Pete]

I have a Bartlein cut rifled barrel, and a Lothar button rifled barrel.................the Bartlein doesn't collect copper, the Lothar does, by the bucketful............

Both will shoot 1/2 MOA groups.

Re-Pete

[SBP]

That's interesting, wonder if Lothar skip the hand lapping part which explains the copper build up?

[bradders]

11 hours ago, Re-Pete said:

I have a Bartlein cut rifled barrel, and a Lothar button rifled barrel.................the Bartlein doesn't collect copper, the Lothar does, by the bucketful............

Both will shoot 1/2 MOA groups.

Re-Pete

So if both shoot the same and one holds tons of copper, then that is obviously a better barrel and not worth the premium cost for the sake of a bit of cleaning!!!!!

[Deserttech Europe]

what is this "cleaning" you speak of ??

[SBP]

I saw on here the review of a Sassen 6.5 cut rifle barrel and that seemed to clean out in 5 patches from the photo. that's got to help in some way I guess?

[VarmLR]

I have a L-W barrel and it doesn't copper up badly at all.  Once of the easiest to clean that I use.

Cut, buttoned, hammer forged, whatever.  You'll find examples of all of them that are extremely accurate.  How they're finished and subsequently treated seems to count for a lot.  I wouldn't get overly precious about needing one over the other...and to upset the apple cart there's now the Sabatti cold hammer forged MRR...initial reports seem to be extremely positive about this barrel form... ?

[Re-Pete]

6 hours ago, bradders said:

So if both shoot the same and one holds tons of copper, then that is obviously a better barrel and not worth the premium cost for the sake of a bit of cleaning!!!!! 

Yep, that's about the size of it, although I'm using Bergara now. Cheap as chips............we've just had one put on our Savage 12 F/TR in 65.x47. (28"  8 twist straight taper).

VERY accurate, a couple of <1.0 MOA groups at 600yds with 136 grain Scenars last week, shot off a bipod and butt bag.

Re-Pete

[meles meles]

With modern manufacturing techniques and quality control, oomans, all barrels should be good and entirely capable of sub minute accuracy. Each production method has its own theoretical advantages and disadvantages but the governing factor is now likely to be how it is used. If you take two identical barrels and shoot them differently you'll probably get very different results.  For example, a barrel shot once a day during a hunt will behave differently to a barrel shot every 20 or 30 seconds for an hour during target shooting. How, and with what you clean it, if at all, will also give rise to differences. Our advice is to ignore the manufacturing technique, find a barrel that shoots well for your needs and enjoy it.  

 

We're contemplating setting a MSc task for the metallurgy students at the Badgerkadamy to study this, or that other old chestnut, "breaking in a barrel" next semester...

[Re-Pete]

I appreciate that whereas we were very happy with the attached card, a lot of competitive shooters most certainly wouldn't be......................but then we only shoot for fun,  to see how good we can get with what we have, and without spending a kings ransom.................

And we don't subscribe to any quasi-religious cleaning rituals or barrel breaking in procedures. Just a wipe through with iso-propanol, followed by an an oily  patch after each session, and an ammoniacal copper remover when the Hawkeye tells us it's needed.

The only thing a clean patch tells you for certain, is that the patch is clean...............

Re-Pete

 

[lee w 118]

54 minutes ago, Re-Pete said:

I appreciate that whereas we were very happy with the attached card, a lot of competitive shooters most certainly wouldn't be......................but then we only shoot for fun,  to see how good we can get with what we have, and without spending a kings ransom.................

And we don't subscribe to any quasi-religious cleaning rituals or barrel breaking in procedures. Just a wipe through with iso-propanol, followed by an an oily  patch after each session, and an ammoniacal copper remover when the Hawkeye tells us it's needed.

The only thing a clean patch tells you for certain, is that the patch is clean...............

Re-Pete

 

The quote above is a about as good as any quote you will ever want to hear , but not off a gun smith, gud on ya pete?

[meles meles]

30 minutes ago, lee w 118 said:

The quote above is a about as good as any quote you will ever want to hear , but not off a gun smith, gud on ya pete?

Us 'umble metallurgists would tend to back 'im up !

[SBP]

Thanks for all the reply's, and I know there's a lot of experience being put into this thread.

But I cant help think, that a single point of cut, from a carbide cutter, with the right helix angles for twist of barrel produces a better stress free groove than pulling a carbide button, with say 15 tons of force, through a barrel bore, even when heat treated afterwards.

 

 

[meles meles]

Machining isn't stress free, ooman. Cutting a groove will produce different stresses than those made by a button. Which is the better process depends upon many things and there isn't s specific right or wrong answer.  Most would assert that cut rifling is the pinnacle of rifling technologies but .... 

Consider the button process for a moment. An oversize carbide button is pulled through an slightly undersize bore, forcing it to take up a new shape. That will certainly leave stresses in the barrel. However, those stresses will be putting the surface of the bore into compression which can be quite a nice situation to be in when you then pressurise the barrel to, say, 55,00 psi. Before any crack can open up and try to blow the barrel apart it has to overcome that residual compressive stress...  In addition, the action of the button as it passes through the bore will have  tendency to deform each individual grain of steel in the vicinity of each grain boundary and partially close up exposed grain boundaries. That gives a smaller surface area of grain boundaries for those supersonic, 2,000 degree plus, erosive / corrosive propellant gases to work on. 

In practical terms, a well made barrel from a recognised maker will almost always be capable of better performance than the user, irrespective of  the rifling technique. If money were no object, and we were a good enough shot to justify the cost, we'd have our barrels made from a PH grade stainless steel by cold flow forming and then clean them once in a blue moon.

[bradders]

Barrels don't know whether they're stressed or not, in the same way they don't know whether they're dirty or clean

I've yet to see a test with a stressed vs unstressed barrel, but I do know it's all academic as a good shooter will always shoot better with a mediocre barrel than a mediocre shooter will do with a good barrel......and there's a lot of mediocre shooters out there..but there aren't that many mediocre barrels

 

[Andrew]

17 hours ago, Re-Pete said:

I appreciate that whereas we were very happy with the attached card, a lot of competitive shooters most certainly wouldn't be......................but then we only shoot for fun,  to see how good we can get with what we have, and without spending a kings ransom.................

And we don't subscribe to any quasi-religious cleaning rituals or barrel breaking in procedures. Just a wipe through with iso-propanol, followed by an an oily  patch after each session, and an ammoniacal copper remover when the Hawkeye tells us it's needed.

The only thing a clean patch tells you for certain, is that the patch is clean...............

Re-Pete

 

Yup. This speaks for me as well.~Andrew

[Re-Pete]

Which brings me on to another question............profiling barrels. Is there any evidence that fluting a barrel will adversely affect the way it shoots?

What about re-profiling from, say, straight taper to medium varmint or palma profile? Is that likely to alter the shooting characteristics of the original?

Re-Pete

[bradders]

1 hour ago, Re-Pete said:

Which brings me on to another question............profiling barrels. Is there any evidence that fluting a barrel will adversely affect the way it shoots?

What about re-profiling from, say, straight taper to medium varmint or palma profile? Is that likely to alter the shooting characteristics of the original?

Re-Pete

I don't think it makes the slightest difference

All barrels start out as oversize straight blanks from the crucible and get profiled to whatever, and fluting is in most cases the final process before chambering.....but sometimes after

Barrels are a consumable with a life of say, 2000-6000rds dependant on various factors, so get your barrel, be happy with it and change it when the time comes

[Chanonry]

2 hours ago, Re-Pete said:

Is there any evidence

None at all mate. Lots of pseudo science p*sh merely repeating t'internet perceived wisdom in a self-aggrandising way.

[No i deer]

I have 2 bartleins and a pacnor.i would say the pacnor crown cleans off easier but the bore is hard to say as the bartleins burn a 1/3rd more powder .there all easy enough too clean.the more shots inbetween cleans the harder it will be to clean.i clean after every range day.approxaimetly 37 to 60 shots between cleans per barrel

[treetop]

Personally, I think it's more of a placebo effect... 

If you are really happy with all your kit, you will be confident & confidence breeds success. The same as doubt will eat away at you. 

That and the fact that 90% of shooters are tarts, we all love a toy ! 

If it looks good, feels good & it puts a smile on your face when it's all going well - then you will sware by the tools that you have, that they are the best.

but like all things, it's easier to blame a barrel or any other part, than blame yourself. Likewise it's easier to change a barrel than it is to go back to basics & learn the fundamentals of marksmanship. 

I would also also add that the workmanship of the gunsmith in cutting the chamber & assembling the rifle will have a lot more bearing in its accuracy than the method used to make the rifling.

 

[meles meles]

17 hours ago, Chanonry said:

None at all mate. Lots of pseudo science p*sh merely repeating t'internet perceived wisdom in a self-aggrandising way.

Yes, plenty of good scientific evidence, some of it even in the public domain.

Consider the L30 CHARM rifle on a Challenger tank. It's a big, heavy barrel that needs to be stabilised so it can fire accurately on the move. That requires the barrel to be have the least weight possible such that the servos and actuators  in the stabilisation system have a chance of keeping it on target. An ideal candidate if ever there was one for fluting. Unfortunately, when a fluted barrel was trialled it had very poor accuracy. The machining of the flutes in a barrel changes the stress pattern within it, and those stresses will be changed asymmetrically too. Thus, as the barrel warms and cools (and that can be due to having the sun on one side and the other in shadow, never mind the effects of firing a round !), it will bend slightly. That is why the Challenger tank has an unfluted barrel, with a thermal sleeve over it to maintain as even a temperature as possible, and a muzzle reference system that uses a laser to measure the amount of bend in any case and let the gunner know where the muzzle is really pointing. 

Moving down in scale, a trial was conducted on small arms.  You know, just to see if "the barrel knows it is under stress"    ?      A laser mounted (rigidly) to the receiver of a rifle and a second to the barrel, equally rigidly. Both collimated to converge at the same spot. Place aforesaid rifle in sunlight for an hour. Both laser dots now no longer concentric. The sun heats up the side of the barrel exposed to it and so that side of the barrel expands by a small amount. However, the 'warm' side of the barrel is constrained by the 'cold' side of the barrel and that doesn't expand as much. The barrel therefore curves a little. It's no longer pointing to the same place it did when it was zeroed. Repeat the experiment with a fluted barrel. The effect was greater.  Those trials data were made available to the manufacturer of a premium grade sniper rifle. That manufacturer no longer offers fluted barrels. 

For most shooters, the above is irrelevant. Your rifle barrel will be capable of shooting with greater accuracy than you can utilise. Bradders summed it up quite eloquently: "a good shooter will always shoot better with a mediocre barrel than a mediocre shooter will do with a good barrel......and there's a lot of mediocre shooters out there..but there aren't that many mediocre barrels."