Barrel Selection Question: Contouring and Rifling

[Jethatsme]

Hello Hide Members,

Decently new to ELR shooting. Here in Florida I has access to a 500 yeard outdoor range, 1300 yard facility and out to a mile within a 3 hr drive. I am looking at getting a new barrel for my Tikka Rifle and had a few questions for the forum:

-Contouring: How does the countour of the rifle affect my accuracy (if at all). I see Medium, and Heavy Contours offer but not entirely sure the difference as it relates to performance
-Barrel Rifling: I see descriptions for barrels like Cold Hammer Forged. 5R Rifling, Stainless Steel, Lapped Barrels. As it relates to pure accuracy, what should be the rifling aspects that I should be most concerned with? If you have an in depth perspective of these different processes or rifling types but I understand that may be asking alot from the forum
-Brand: Schillen, Bartlein, Krieger, Dougla. Does the brand at this level of barrel really matter or is it more the configuration of the barrels specs?
- Fluting: Will fluting a barrel affect its performance?


A few facts to guide the discussion:

Purpose: Shooting Medium to Small steel targets from the prone position or off varying types of terrain. No Competition, No Hunting. Perhaps occasional 3-day hiking precision class
Caliber: I will be getting a barrel for both and 6.5 Creedmor and 338 Lapua setup (338 will be a separate rifle all together)
Reloading: I do not plan on reloading myself unless I am paying someone to reload rounds for my rifle (Unlikely for now)
Barrel Length: Barrel will be 24" or 26" inches

I realize these may be a basic questions so forgive me.

 

[TheOE800]

I myself am newer to this, but below is what I've found in my research. I welcome corrections and more information.

Contour: Beyond simply the weight, this impacts the vibrations of the barrel after firing and correlates to stiffness of the barrel. Length and stiffness are inversely related: As length of the barrel increases the stiffness decreases. However, the thickness is directly related to the stiffness: A thicker barrel will be stiffer than a thinner barrel of the same given length. Additionally, the contour is directly related to the heat mass of the barrel - a thicker barrel will take longer to heat up and longer to cool down once it has become thermal soaked.

Rifling: This area requires more precision than you've given. CHF for instance is a way of producing rifling, as are other common methods such as button-rifling and cut-rifling. This differs from things such as 5R, ratchet rifling, traditional/standard rifling patterns that describe the arrangement of the lands and grooves of the rifling in the bore of the barrel rather than the method used to produce the arrangement.

Brand: The manufacturer of the blank matters more than the features, IMO. There is a difference between the many manufacturers, but once you get to a certain level they are considered in the same league. A well known gunsmith told me he offers three particular manufacturers with no guarantee as to which blank you get as he has seen no difference at that level; people waiting on a particular blank caused loss of customers, unreasonable wait-times, etc. so he simply gave his customers the choice of contour, length, and chambering of several quality manufacturers he regularly stocked.

Fluting: Define performance. For one, you are removing heat mass from the barrel, but you are increasing its surface area; therefore, the barrel may heat up quicker, but should cool down quicker as more surface area is exposed to the air. Of course, you are reducing weight as well which can be important depending on the rifle's use. As far as harmonics and stiffness, I have no information on that.

Essentially, contouring and rifling of a barrel come to your preference, superstition, and voodoo magic.

 

[Supersubes]

It used to be fairly standard to use a heavy straight taper like a m40/m24 contour when building a custom or rebarreling. That has evolved a bit towards lighter weight. The most popular contour is probably a rem varmint/sendero or the medium palma, which is functionally identical. For your usage on the creedmoor, id go towards the lighter end of things, thats just me. You'll lose no accuracy with the palma or rem varmint type contours.

As far as american barrel makers go, you wont find any of the match barrel makers hammer forging barrels. Not that its bad, its simply a high tech way of making large quantities of barrels. The major firearm manufacturers use that method. That leaves cut or button rifling. Most people have a preference, but I bet few if any could shoot the difference in a field rifle. I dont personally think it matters at all, but i do have a preference for cut rifling if Im being picky. I think the process is just cool. Most all the top end makers lap their barrels, usually in the very last step of manufacture. Douglas, i believe, does not. Their button rifle process produces a finish they like. As Americas oldest button rifle barrel maker, they have a lot of fans, and are stocked by some of the major vendors like brownells. I havent chambered one yet, but i plan to. Never been a better time to buy a custom barrel. There are a bunch of new makers out there doing really good things

Rifling profile, like contour, doesnt really matter. Appropriate twist for your intended projectile/velocity is what matters. There are lots of shapes out there. Some generally associated with a certain process. 4 groove is common used by cut barrel makers. 3 or 6 groove are typically used by button barrel makers.

You can learn a lot from reading the barrel makers websites. Quite packed with info usually, and i find them interesting. Ive had many nice phone conversations with many of them over the years. You'll notice each maker tends to use a certain type of rifling profile. There are lots of good barrel makers out there. In benchrest shooting, bartlein and kreiger dominate(cut rifled), which is an evolution over the last 20 years or so, because shilen and Hart used to dominate(button rifled).

Never a bad thing to simply go with the gunsmiths recommendation either. They tend to gravitate towards things that produce results for them. If for whatever reason, you get a dud, you'll have the guy doing the machine work in your corner when it comes time to address it with the barrel maker.

Fluting looks bitchin for sure, but it does nothing in my opinion. I think the "more rapid cooling" thing has been debunked at this point. Accuracy international tested fluting, and found it caused deviations. Buuuuuut, there are lots of fluted barrels out there kicking ass. Save the $150 bucks and spend it on the next barrel.

 

[vh20]

Great advice given above in both posts. Regarding the gunsmith that offers three different barrel possibilities with no guarantee as to which, my gunsmith does the same thing (unless you specifically are willing to wait for a particular brand to be available). The three are Rock Creek, Bartlein, and Krieger, (all cut-rifled).

For my .338 I went with 26 in. M24-contour, fluted, Rock Creek. For my 6.5 I went with 26 in. Remington Heavy Varmint-contour, fluted Krieger. (Remember, if you go down in bore size, you have to go down in contour if you are trying to keep the same weight and rigidity. Otherwise, a 6.5 M24 would weigh more and be more rigid than a .338 M24 of the same length).

Regarding fluting, it's "probably" best if the manufacturer does it rather than the smith. Krieger says that if they flute one of their barrels, they don't do the lapping until after the fluting is done, in case any internal stresses were introduced. If a smith flutes a barrel, it's probably best to keep it fairly shallow (and that's what we had to do on my Krieger because a factory-fluted one wasn't available).

 

[Jethatsme]

Guys really great insight. Thanks for providing such detail. As Supersubes mentioned the Manufacturer websites are filled with excellent information. The information on the website combined with the explanation here help a lot in connecting the dots. I would always get confused when certain process specific terms were mentioned in a description and it would be like reading a foreign language. For now, I am making an excel with some of the different factors and categorizing my choice accordingly. Will let you know what I got with for both options.