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Old 03-01-2012, 10:15 AM   #11
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Originally Posted by cfraga1978

Havoc you better hurry and post something else you are at 666 posts.

Maybe we should break twist rate down a bit more - 1:7= fast spin (heavy bullets) 1:12= slower spin (lighter bullets). If you shoot light weight bullets 40-50 gr with 1:7 the bullet can rip itself apart and if you shoot a heavier bullet 70-90 gr it may not stabilize and tumble in flight. That is as simple as I can put it.
So is it safe to think that I would need to know what type of ammo I wanted to shoot first to know what type of barrel twist I should be using or is that over thinking it too much?
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Old 03-01-2012, 01:38 PM   #12
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Originally Posted by ar15noob

So is it safe to think that I would need to know what type of ammo I wanted to shoot first to know what type of barrel twist I should be using or is that over thinking it too much?
Not so much.. you need to know what type of shooting you are going to be doing and at what ranges. You have a lot of overlap between them. I shoot a 1:9 and it likes 40 up to 70 grain bullets and a 1:7 may like 55 up to 90 grain. I have heard a 1:8 is a good all around twist.
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Old 03-01-2012, 01:49 PM   #13
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It will vary from barrel to barrel even with the same twist . I have 2, 1:7 twist barrels one shoots 55 gr FMJ fabulous the other doesnt group well unless Im shooting 62 gr. both barrels are from the same manufacturer so you truley wont know what shoots best until you try it .

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Old 03-01-2012, 02:24 PM   #14
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Originally Posted by AgentTikki View Post
just to be clear, its not really the weight of the projectile, so much as the length....
True, but within a given caliber, higher weight typically translates to a longer bullet. The only variances are when switching between FMJ and HP.

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Old 03-01-2012, 04:55 PM   #15
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Quentin.....nothing nefarious meant here. Truly a noob with questions...as you have seen and responded to my other ones this past week or so. Admittedly the title should have been worded better and with a question mark. I appreciate all the responses and look forward to my purchase.
Fair enough and I shouldn't single out just you, AR. It's just a trend I've seen here and elsewhere. Seems like the title of the thread should try to summarize the content and whether it's a question or a thesis.
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Old 03-02-2012, 02:37 AM   #16
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Originally Posted by cfraga1978

Not so much.. you need to know what type of shooting you are going to be doing and at what ranges. You have a lot of overlap between them. I shoot a 1:9 and it likes 40 up to 70 grain bullets and a 1:7 may like 55 up to 90 grain. I have heard a 1:8 is a good all around twist.
Thanks a million cfraga this helps a bunch defining grains and twists.
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