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Old 12-28-2011, 03:16 AM   #21
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The SF guys used match grade stuff when I was in. They gave us a small lot of it as we began to run low. It was heavier than our green tip but I don't remember what grain.

If NATO would get w/ the times and remove ammo restraints it would sure level the playing field.

We all used 1:7
I'm pretty sure it's 77gr OTM.

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Old 12-28-2011, 03:56 AM   #22
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I'd like to see the guys able to use some ballistic tip ammo. I honestly don't recall a time when barrier penetration was needed when an AT4 wasn't available.



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Old 12-28-2011, 12:12 PM   #23
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The .223 Rem shoots a wide range of bullets very effectively, from 35gr flat-based varmint bullets, to ultra-long 90gr VLDs. However, you'll need the right twist rate for your choice of bullet. For max velocity and accuracy with the lightest bullets, a 1:14" twist may be ideal. More versatile is a 1:12" twist that will allow you to shoot the popular 60-64 grain match bullets. (However, a 1:9" twist is needed for the steel-core 62gr bullet used in the M855 military loads, because that bullet is as long as most 70-grainers.) For normal lead-core jacketed bullets, a 1:9" twist will let you shoot up to 73gr bullets. Since most .223 Rem shooters prefer bullets in the 50-73gr range, a good "do-it-all" solution is a 9-twist, unless you're a Highpower competitor.

For long-range match purposes, long, high-BC bullets are favored for their ability to buck the wind. You'll want at least a 1:8" twist to shoot the 77gr and 80gr MatchKings and 80gr Bergers. To shoot the new 90gr pills, a 1:6.5" is recommended, though a true 1:7" will work in most conditions.

Overall, what twist rate is best? For varminting we like a 12-twist. The slower twist will give you a bit more velocity, and minimize the risk of jacket failure at high rpms. For general use, an 8-twist barrel will let you shoot the excellent 77gr and 80gr Sierra MatchKings and nearly all varieties of non-tracer milsurp ammo. We'd only select a 1:7" or faster twist barrel if we had a need to shoot the 90gr VLDs.

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Old 12-28-2011, 12:55 PM   #24
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The .223 Rem shoots a wide range of bullets very effectively, from 35gr flat-based varmint bullets, to ultra-long 90gr VLDs. However, you'll need the right twist rate for your choice of bullet. For max velocity and accuracy with the lightest bullets, a 1:14" twist may be ideal. More versatile is a 1:12" twist that will allow you to shoot the popular 60-64 grain match bullets. (However, a 1:9" twist is needed for the steel-core 62gr bullet used in the M855 military loads, because that bullet is as long as most 70-grainers.) For normal lead-core jacketed bullets, a 1:9" twist will let you shoot up to 73gr bullets. Since most .223 Rem shooters prefer bullets in the 50-73gr range, a good "do-it-all" solution is a 9-twist, unless you're a Highpower competitor.

For long-range match purposes, long, high-BC bullets are favored for their ability to buck the wind. You'll want at least a 1:8" twist to shoot the 77gr and 80gr MatchKings and 80gr Bergers. To shoot the new 90gr pills, a 1:6.5" is recommended, though a true 1:7" will work in most conditions.

Overall, what twist rate is best? For varminting we like a 12-twist. The slower twist will give you a bit more velocity, and minimize the risk of jacket failure at high rpms. For general use, an 8-twist barrel will let you shoot the excellent 77gr and 80gr Sierra MatchKings and nearly all varieties of non-tracer milsurp ammo. We'd only select a 1:7" or faster twist barrel if we had a need to shoot the 90gr VLDs.
Best answer so far, good job!!!!
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Old 12-28-2011, 01:23 PM   #25
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The way twist rates was explained to me is that we would like the bullet to always be pointed in the direction of travel so we spin stabilize it. However, bullets don't travel in straight lines as the fly through an arc. So, ideally, it spins at just the right speed to be stable enough to not wobble but be able to let the forces of air turn it slightly to follow the arc. So, an overstabilized bullet will want to stay pointed up at the angle it left the muzzle and, at longer ranges, will be less accurate than a bullet spinning at a more optimal rate. At 100 yds I have no problem with my 1 in 7 twist with 55 grain bullets. I have not experimented with 300 yard shots yet. I plan to use 75 grain bullets for coyote shooting so I went with the 1 in 7 twist.

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I'm looking to do a semi-build on an AR. The Palmetto State Armory complete uppers seem to be getting a lot of good reports and are very reasonably priced. But it seems everything they are making is in a 1:7 twist. This seems pretty aggressive for a general purpose carbine.

Would you be concerned about 55 grain bullets with a 1:7 twist? Or should I really be looking for a 1:8 or 1:9?

My intent is a rifle that will be used for plinking, HD, and coyotes. I'll probably look at a different upper for varmints down the road.
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Old 12-28-2011, 01:40 PM   #26
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Quote:
Originally Posted by mjkeat View Post
The SF guys used match grade stuff when I was in. They gave us a small lot of it as we began to run low. It was heavier than our green tip but I don't remember what grain.

If NATO would get w/ the times and remove ammo restraints it would sure level the playing field.

We all used 1:7
NATO does not have anything to do with the ammunition restriction. It is international law (Hague Accords) that outlawed frangible ammo against enemy combatants. IMHO this does not apply to insurgents. Give them the OTM!
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Old 12-28-2011, 02:04 PM   #27
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NATO does not have anything to do with the ammunition restriction. It is international law (Hague Accords) that outlawed frangible ammo against enemy combatants. IMHO this does not apply to insurgents. Give them the OTM!
ooopss.

I never got into that, I was busy shooting bad guys in their faces . Actually center mass or wherever, it didn't matter.
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Old 12-29-2011, 03:51 AM   #28
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I have a 1 in 7 spikes. All 55 gr federal bullets made it to the paper.
I have also shot some 55 gr wolf HP boat tail steel jackets, also made
it to the paper at 100yards. Never shot anything weighing less. Now
that I've seen that video, I kind of want to try.

1 in 7 works for the military, got to be good enough for me right?

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Old 12-29-2011, 04:42 PM   #29
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Mil Spec is 1:9....and so that is good enough for me. I can shoot 55s or 62s just fine.

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Old 12-29-2011, 05:05 PM   #30
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Mil Spec is 1:9....and so that is good enough for me. I can shoot 55s or 62s just fine.
Interesting. Where do you get your information?


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