FAQ Why do you offer so many choices in Twist Rate
A. We offer a number of different twist rates in the various calibers that we make. This allows you to pick the optimum rate for the particular bullet you plan to use. This is especially true for target shooters who will probably use just one or two bullet weights and styles for their type of shooting sport.
However if you plan to shoot a variety of bullet weights in your barrel then you must choose the twist rate for the heaviest bullet that you plan to shoot. For example, let’s say that you’re going to build a 300 Winchester Magnum for longer range deer hunting. A bullet weight of 150 grains might be the best choice for your type of hunting. And a 12″ twist would be correct for that bullet. But someday you might hunt elk or moose and think that you might want to use a 200 grain bullet for the bigger animals. Then the twist requirements change and a 10″ rate is the choice. But, you can still shoot the lighter weight bullets in the 10″ twist with good accuracy.
As bullet weights increase the twist rate required to adequately stabilize the bullet increases. The fact is though, that actual bullet weight has little to do with twist. It is overall bullet length that has the most influence on stability. The reason we base twist on weight lies with the fact that bullet length usually increases as weight increases. And some bullets are especially long for their weight. For example the Nosler Ballistic Tip bullets are all longer than comparable weight bullets of another weight because of the plastic tip. And as a result the ballistic Tip bullets sometimes need a faster twist rate than is normal.
Target shooters, especially bench rest shooters, like to use the slowest possible twist rate they can get away with in an effort to get the very ultimate in accuracy from their barrel. For example, most benchrest shooters using the 6PPC cartridge and 62-68 grain hollow point flat base bullets use a twist rate of 13-14″ and some even use a 15″ twist! For normal target shooting, varmint hunting and big game hunting though, it is much better to go with a twist rate that is on the fast side rather than the slow side. While that 15″ twist 6mm barrel we just mentioned might do well on a nice warm summer afternoon on the benchrest range, the same combination might shoot wildly on a cool spring morning of wood chuck shooting.
When twist rates are offering marginal stability atmospheric influences such as temperature, altitude, and even normal fluctuations in the barometer can have noticeable effects on the target. As the temperature and altitude go up so does bullet stability for a given twist rate. Conversely, a lowering of the barometric pressure increases stability.
The newer VLD design bullets require a faster twist rate than is normal for their particular bullet weight and caliber. But with high quality bullets accuracy is still very good.
Choosing the correct twist rate for your barrel is an important consideration. To help you choose the correct rate we’ve made up the following chart. If you have any questions, please ask.
RECOMMENDED TWIST RATES
Grain/Cal |
.172 |
.204 |
.224 |
.243 |
.257 |
.264 |
.277 |
.284 |
.308 |
.338 |
.358 |
17-20 |
9-10 |
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|
|
|
|
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25 |
10 |
|
|
|
|
|
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|
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|
30 |
9 |
12 |
|
|
|
|
|
|
|
|
|
33 |
|
12 |
|
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|
|
|
|
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|
|
35 |
|
12 |
|
|
|
|
|
|
|
|
|
37 VLD |
6 |
|
|
|
|
|
|
|
|
|
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40 |
|
12 |
|
|
|
|
|
|
|
|
|
50-52 |
|
9 |
14 |
|
|
|
|
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|
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|
55 |
|
|
12 |
|
|
|
|
|
|
|
|
60 |
|
|
12 |
|
|
|
|
|
|
|
|
68-69 |
|
|
9,10 |
13,14 |
|
|
|
|
|
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|
75 |
|
|
9 |
|
14 |
|
|
|
|
|
|
80 |
|
|
8 |
|
|
|
|
|
|
|
|
85 |
|
|
7 |
12 |
12 |
12 |
|
|
|
|
|
90 |
|
|
7 |
10 |
|
|
|
|
|
|
|
100 |
|
|
|
10 |
10 |
|
12 |
14 |
|
|
|
105-107 |
|
|
|
8 |
|
|
|
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|
|
|
120 |
|
|
|
|
10 |
10 |
|
12 |
15,16 |
|
|
130 |
|
|
|
|
|
|
10 |
|
14 |
|
|
140 |
|
|
|
|
|
9 |
10 |
10 |
|
|
|
150 |
|
|
|
|
|
|
|
|
14 |
|
|
140-160 |
|
|
|
|
|
8 |
10 |
10 |
12,13 |
|
|
150-168 |
|
|
|
|
|
|
|
9 |
11,12,13 |
|
|
150-180 |
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|
|
10,11,12 |
|
|
160 |
|
|
|
|
|
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|
9 |
|
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|
175 |
|
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|
9 |
|
|
|
180 |
|
|
|
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|
|
|
|
10,11,12 |
|
|
200 |
|
|
|
|
|
|
|
|
10,11 |
10,12 |
12,16 |
220 |
|
|
|
|
|
|
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|
10 |
|
|
225 |
|
|
|
|
|
|
|
|
|
10,12 |
12,16 |
240-250 |
|
|
|
|
|
|
|
|
10 |
10 |
12 |
300 |
|
|
|
|
|
|
|
|
|
10 |
12 |