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Posted By: Tracks Barrel lenght and twist rate - 04/26/03
I'm planning to have a 338/06 built on a Rem 700 action. and I'm thinking a 210 gr Nosler would be my prefered bullet. I would like a short heavy barrel as well but I'm not locked into that idea
What would be the optimum barrel lenght and twist for that caliber/bullet combo?
Any barrel length from 22 to 28 inches would be good. The best compromise between velocity and accuracy would probably be 24 inches.

To get the range of appropriate twists (minimum and maximum) in inches, square the diameter of the bullet (multiply it by itself), divide the result by the length of the bullet, and then multiply the result of that calculation first by 150 for the shortest appropriate twist, then by 200 for the longest. The longer twists in this range will be the best for adequately stabilizing the bullet without over-stabilizing it and thereby reducing its effective range. I don't think you'll have to worry about spinning the bullet too fast for it to hold together, which is another matter subject to other calculations.
I can do that. Thank you
With the interesting application of the Greenhill formula the question on twist is perfectly answered.

Please let me add some words on barrel length.

The decision for a longer or shorter barrel is often bound to the purpose of the rifle.
As a hunter you're going for a short, i.e. light and handy, rifle, but as a Long Range competitor you may want to make use of the extra fps a long barrel provides plus the better alignment of sights (does not apply to scopes).

When you happen to have a look at a pressure/barrel length diagram, the area underneath the pressure curve is the pressure. When this diagram is laid out for a 32" barrel and you consider to make use of a 24" barrel, you see immediately how much pressure = powder (this is the area between the 24" mark and the muzzle) you give away unused - and even worse: the heavier muzzle blast may give your bullet an unwanted kick which may causes a disturbed departure.

Not enough complications yet: when you start considerations on barrel vibrations, your question has the potential to become very difficult and moorish.
Interesting addition, but I think I will go with a fairly heavy 22 inch free floated barrel. As to vibration, as long as the bullet leaves at the same point of the shift every time I can adjust for it
I have long fast rifles and and short handy ones, but on this one I want repeatability for the average mid range shot, something in the '06 speed range but with a bit more frontal area. I also really like the 338 bullets
Best of all it lets me get rid of that *><# *ing 270 without having to use a torch on it.
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The .338-06 has a bore/case capacity ratio about like the .308 Winchester, which operates quite well in a 22" or even shorter barrel. In fact the .338 Winchester Magnum itself does very well in a 22" barrel, because it's bore/capacity ratio is about like the .30-06's.

I think you'll be very happy with a fairly heavy 22" barrel. I built a .338-06 just like that with a #4 Douglas and it shot very well with any bullet from 200 to 250, and generally into the same point of impact. I could never tell the difference, and I've had 24" .338-06's too. Evidently the differences in individual barrels can greater than the 2" in barrel length.

JB

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