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Old 08-06-2010, 03:38 PM   #91
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So a heavier bullet needs a faster rate of twist to stablize? Given the same barrel length and target distance.

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Old 08-06-2010, 03:41 PM   #92
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bullet weight has little to do with twist.

Bullet length has a lot to do with twist rate. Most people equate longer bullets with heavier bullets.

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Old 08-06-2010, 03:44 PM   #93
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Originally Posted by spittinfire View Post
So a heavier bullet needs a faster rate of twist to stablize? Given the same barrel length and target distance.
Basically, that is a pretty good statement. What you are looking for is a bit faster spin. Like in a .308, there is a 1:12 and a 1:11 and a 1:10 twist rate barrel. The 1:12 is good for the standard 168gr rounds ( usually ) but if you step up in grain to the 175gr, you might get better accuracy out of 1:11 or even 1:10 depending on the barrel maker and consistancy of the cartridges, etc.

That doesn't mean you can't achieve good accuracy with a 1:12 and shooting a heavy bullet, but you might be able to achieve THAT much better accuracy if the bullet was spinning just a bit quicker.

I am not a big math guy, but there is a formula that was developed that I have heard of that is supposed to be able to help you dial in the bullet you are wanting to shoot, with the barrel twist rate you should buy.

Here is the formula calculator that I found on line. Barrel Twist Calculator
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Old 08-06-2010, 03:45 PM   #94
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bullet weight has little to do with twist.

Bullet length has a lot to do with twist rate. Most people equate longer bullets with heavier bullets.
My "bullet" is long AND heavy...
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Old 08-06-2010, 03:53 PM   #95
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OK, so what about the variable twist rate barrels? Any credibility? Or voodoo science?

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Old 08-06-2010, 04:05 PM   #96
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My "bullet" is long AND heavy...
And goes off at the slightest stimulation of the primer....
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Old 08-06-2010, 04:13 PM   #97
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And goes off at the slightest stimulation of the primer....
At least it's better than being a dud...
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Old 08-06-2010, 04:14 PM   #98
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Quote:
Originally Posted by cpttango30 View Post
bullet weight has little to do with twist.

Bullet length has a lot to do with twist rate. Most people equate longer bullets with heavier bullets.
Given a bullet of the same caliber and material how else would you alter the weight except with lenght?

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Originally Posted by Dillinger View Post
Basically, that is a pretty good statement. What you are looking for is a bit faster spin. Like in a .308, there is a 1:12 and a 1:11 and a 1:10 twist rate barrel. The 1:12 is good for the standard 168gr rounds ( usually ) but if you step up in grain to the 175gr, you might get better accuracy out of 1:11 or even 1:10 depending on the barrel maker and consistancy of the cartridges, etc.

That doesn't mean you can't achieve good accuracy with a 1:12 and shooting a heavy bullet, but you might be able to achieve THAT much better accuracy if the bullet was spinning just a bit quicker.

I am not a big math guy, but there is a formula that was developed that I have heard of that is supposed to be able to help you dial in the bullet you are wanting to shoot, with the barrel twist rate you should buy.

Here is the formula calculator that I found on line. Barrel Twist Calculator

I may have to play with that. I shoot 150gr bullets for deer here in NC from my ATR with 1:10 twist. I played with some 180s I got somewhere and actually had a tighter group but 180 at the ranges I shoot is overkill.
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Old 08-06-2010, 04:17 PM   #99
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At least it's better than being a dud...
Ladies love the dud. I can chamber it over and over, ALL...NIGHT...LONG!!!
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Old 08-06-2010, 04:22 PM   #100
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Originally Posted by c3shooter View Post
It is legal to poach eggs, so that the salmon does not get lonely.
Why are salmon so lonely?
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