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Old Sheepdog
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Whats your favorite bbl. rifling twist rate with which favorite bullet wgt. in a .223 AR-15? Tracy
 

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most 223 / 5.56 come in 1 and 9 .. match 1in 8 and mil are 1 in 7

i use a 55 grain in my 1 in 9 have not tried the heavier bullets yet

the original ar were 1in 14 then 1 in 12

i would have to get the ar book im reading to tell you the optimal weight for twist
 

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I'm new at this but I been studying hard on this very subject...

I think 1 in 9 is the best option for what we are going to use it for...it will stabilize bullets from 50 to 70 grains...and the part that sold me on 1 in 9 is that its easier on the throat of the barrel (IT LASTS LONGER)...having said that I havent tried them yet but Federal offers a 60 grain Nosler Partition load... also, for reloading, Barnes Triple Shock in both 62 and 70 grains (<<<Deer loads)...I'm betting that the 62 grain bullets will be the most accurate for the 1 in 9.
 

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Old Sheepdog
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1 in 7, 72g bullet
 

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Truthfully twist wont matter for throat wear its loads FPS and how hot you let the barrel get and how fast you shoot that causes Chamber throat wear ..
 

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Truthfully twist wont matter for throat wear its loads FPS and how hot you let the barrel get and how fast you shoot that causes Chamber throat wear ..
Generally yes...you're right... but think about it...the faster the twist, the the more stress on the rifling near the throat, trying to get the bullet spinning...it seems to be popular opinion that 1 in 7 is harder on the first few inches of rifling...thats why you dont see any 1 in 9 barrels made from 4150 CMV steel, and nearly all 1 in 7 barrels are 4150 CMV.
 

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Never have read that so dont know ... But usually 1 in 7 is with 3 round burst or full auto ..

I still say its how ya treat it my bushy still shoots great after all these years and round course i dont abuse it .. it is 1 in 9 ... Im reading the ar books .. right now you can get them from fulton armory ill tell ya what they say about it ...


Also if you read up on some of the barrel burners 220 swift etc etc they always tell you its shooting and overheating the barrel and a 220 swift makes a 223 look slow

220 swift is running 1 in 16 and 1 in 14
 

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The Swift is 4000+ fps and yes its a barrel burner...after 2 barrels I got rid of mine.

Its just that 1 in 7 puts more stress on the first few inches of rifling...I read it in a few different threads over on m4carbine.net....those guys seem to know their stuff, and everybody seemed to agree with it.

I'm no expert on it either...but 1 in 7 is a FAST twist.
 

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I could see it doing more damage tot he bullet than the barrel copper is weaker than steel .. Maybe it does make a difference but i don't see how it still takes heat to waste a throat..

unless they are saying the 1 in 7 twist is slowing the bullet enough to increase chamber pressure and heat long enough to torch the Throat and the extra heat from the bullet maybe
 

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unless they are saying the 1 in 7 twist is slowing the bullet enough to increase chamber pressure and heat long enough to torch the Throat and the extra heat from the bullet maybe
That may be it...
 

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That like a chart i was looking for and couldnt find thanks for link ...


here is the post

y Corey Sattler ([email protected])
Here is the info I have collected for .223 twist ratios from various sources (including in-house testing & ammo manf. contacts).

1x7 - technically too tight of a twist for any .224 bullet widely available, including the 80 gr. Manufactured originally to stabilize SS109 and/or tracer ammo, but further military testing has shown other twists to be superior. Some of the very heavy custom stuff (87 gr?) may work well, but why????

1x8 - great twist for 69-80 gr bullets. Sierra once informed me that the perfect twist for their 80gr was 1x8.2xxxxx (blah blah blah big long engineers explanation followed).

1x9 - good all around twist ratio. Best suited for 52-69 gr, but either end of the envelope will be questionable.

1x10 - practically the same as 1x9, but favors the lighter side a little more.

1x12 - great for the 40-52 gr bullets. Most often found on bolt action rifles as their primary use is varminting. All right for the 55 gr, but not the best.

1x14 - if you want to understabilize the .224 bullet, use this twist. Useless except for tumbling effect it causes upon bullet impact. IMHO, better to shoot straight with a good HP bullet as your chances to hit are better and damage will most likely be greater also.

About the author: Mr. Sattler is the Law Enforcement Sales Manager and Archival Records Manager at Olympic Arms, Inc. in Olympia, WA and has been with the company since 1993. He is also a Reserve Deputy in a small Southwest Washington county Sheriff's Office.
 

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Old Sheepdog
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Discussion Starter #13
Gast,

THANKS! Saved it to my favs. Will refer back to it as the need arises. Thats the info I was looking for. Tracy
 

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twist

Tracy,my varminter is a 1x10 twist but my tactical is a 1x9 twist,both with match chambers,when the weather breaks will take you shooting if you're interested.
 

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Old Sheepdog
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Discussion Starter #15
Gast,

OH YEA! Thanks Tracy
 

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Whats your favorite bbl. rifling twist rate with which favorite bullet wgt. in a .223 AR-15? Tracy

I've had good performance out of both 20" and 16" barrels in 1-7" twist, using bullets from 55gr. to 77gr and a 16" barrel in 1-9"twist using 55gr and 63gr bullets.

Currently I'm using a 1-7 twist 16" barrel.

For my current use I'm loading 55gr FMJBT and 60gr SP.
 

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1:7.7 twist (Krieger stainless) and 69-80 gr. Sierra's....
 

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Twist is not what burns out a barrel. It is powder capacity compared to bullet diameter.
The small diameter of the .220 Swift coupled with the large powder charge forces unburned powder and gas through the small hole eroding the throat and chamber.
The .22-250 uses a smaller powder charge and it is not a barrel burner, also if you download the .220 Swift the barrel life can be normal.
I like 1/7 or 1/9 with 55gr and 69gr bullets for the AR.
 

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My Rock River has a 1/8 twist and my HK93 has a 1/12.

I read that the instability of the bullet in a 1/12 twist caused greater damage on impact and was better at ranges under 300 yards. Any truth to this?
 

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1/14 was the original twist but it wouldn't stabilize in cold environments .. but yes 1/12 is supposed to be less stable and cause more damage
 
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