contour and twist rate .338

[anginaprinzmetal]

I realize this question comes every now and then.
As my background, I shoot regularly in 6.5 Cr and .308 up to +/- 1,000 yds but finally I decided to take it to the next level.

I'm in the process of building long range rifle in a magnum .338 and I realize that these large calibers are a whole different kettle of fish. Pretty humbling actually.

I already have a Defiance Deviant Tactical action and have to decide on the chambering (.338 LM vs .338 NM) and so picking up the barrel has presented me with some questions. What contour should I choose and in order to get the right contour should I compromise in the twist rate. I have found a Bartlein .338 blank with a heavy palma contour (which is what I want) with a 1:10 twist rate or a Sendero (lighter) or an MTU (heavy !!) with a twist rate 9.3

So that the question is should I favor/go with the profile I want (Heavy Palma) and potentially choose the suboptimal twist rate (not sure if this is true though) or choose the "ideal" twist rate and sacrifice on the contour.

Finally, although I'd like to think I am going to go long range hunting with this thing realistically I prob won't. I will however take it out in the desert for long range shooting, sometimes with a hike.

Thanks

 

[TripleBull]

Have you decided on a projectile yet? Do you plan to shoot solids?

 

[anginaprinzmetal]

no decision on projectile yet but I know that I may want the ability/flexibility to shoot different weights. In case I can't reload or I'm out of town or something

 

[vh20]

This isn't going to answer your specific question, but perhaps will give you something to think about in making your decision. The designer of the 338 Norma cartridge prefers an M24 contour, 26 in. bbl with a 1:9.4 twist, with Rock Creek being his particular favorite. Of course, he designed the cartridge specifically around 300 gr. SMKs, so that is what that twist rate is optimized for (the entire cartridge was designed around the bullet).

That's the barrel I went with, and if building another I'd order it and wait for it.

 

[anginaprinzmetal]

how's the weight of that M24 contour? I was thinking .338 Lapua w/ a 28 inch barrel (compromise) so that is something I can still take with me on a short/medium hike.
My concern is would I've giving up accuracy if I go with a Sendero profile (it would taper to 0.875 at 26")

 

[sierracharlie338]

Stick with the M24 you will be happier in the long run. I have an M24 "like" contour on my 338 and I can't imagine shooting it with a sendero contour. I also have a 9.4 twist in mine also and it shoots very well

 

[lash]

Unless you truly plan on hunting with the rifle, in which case a 28" barrel will be a hindrance for hiking anyway, you should stick with the heavier profile. If not properly balanced and shot with good fundamentals, the .338s can be punishing. If you plan on taking it to the desert for a day of shooting, deal with the extra weight and get a heavy profile. I think that you will be glad that you did. The factory Savage barrel that I'm currently shooting is a lighter contour and it heats up quickly when firing more than two or three in a string. When I replace it, it will be with a heavier profile barrel.

Build the rifle with a purpose and projectile (or two) in mind, not some do-everything franken-rifle that doesn't do anything well.

And get the 9.3 twist or there-about. As already mentioned, the 300s like the faster twist, and it will give you the option of using the solids too, which like a faster twist rate. If you stick with shooting the heavy caliber, you'll eventually find yourself wanting to stretch it's legs a bit once you have a handle on the boring inside 1500 yards shooting. If you don't keep at it, the 9.3 twist is more appealing to potential buyers in a longer barrel, IMO.

 

[ZiaHunter]

My 338 currently has a Bartlein 5R 26" heavy palma with a 1:10 twist and handles the 300's just fine. When time to rebarrel will probably chamber it in 300 NM.

 

[anginaprinzmetal]

Thank you all for your answers. After some thoughts, and a phone call to Bartlein, I bought a Bartlein MTU profile with 1:9.3 twist rate. This thing is going to be on the heavy side, but for this type of cartridge it should be ok. I also gives me an excuse to buy a 300 win mag if I ever want to go hunting. Now to decide on the chamber: 338 LM vs 338 NM.

 

[Fursniper]

Just finished the barreled action on my 338 lapua improved, a 32" Krieger, custom profile (1.450 at the breech, 1 inch at the muzzle, straight taper, 9:3 twist. It's a big mamajama, hope it shoots! Weight estimate in the yet to be delivered McMillian supermag, LRA bipod and the gen II razor is 22 pounds finished. Go big or go home, lol.

 

[majohnson2]

Greg at Bugholes built mine using a MTU profile Bartlien 5R. It a 1-9:3 twist with a custom reamer ground to shoot 300gr Berger OTM. The APA Fat Bastard really cuts the recoil. Accuracy even in the wind is half moa or better.

 

[anginaprinzmetal]

what barrel length did you use?
was thinking 28"