twist rate and what grain bullet for 223

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LennyM

New member
I just bought a nice Ar with a douglas barrel,it has a 1/7 twist rate,what is the best weight 223 bullet for this twist rate.I have a load of 40 grain BTs but i think i need a heavier bullet for the best accuracy.Am i correct? this is mostly going to be used for coyotes.
Thanks for your time..
 
It should shoot pretty much everything fine. Personally, I'd be twistin' up some 75gr A-maxes, but you would have to single feed them I guess, because of mag constrictions.

I'm not really an AR guy, but it seems an AR with a standard mag would not be able to take full advantage of a 1-7 twist rate, as far as heavy/long bullets go........

 
Your 1/7 twist is designed to shoot the heavier bullets. You may find that it does not shoot the 40 grain bullets well. Try some 55-68 gainers for best results
 
While we are on barrel twist, how about a 1/10? Does anone make them? Does it develop less pressure and at the same time more velocity for bullets under 60 grains? What say you guys? kwg
 
I think OLY and DPMS both make a 1/10 twist. Most Factory Bolt rifles have a 1/12 twist. 1/9 is a very good option as it will shoot down to 40 grain bullets well and handle most of the heavier stuff that will fit in a magazine.

Twist has only a minor effect on pressure and velocity. Although velocity has much to do with what bullets any twist BBl will shoot. ie a 1-7 may tear 40gr bullets apart unless they are slowed down some and a 1-9 twist my not stabilize a 69grain+ bullet unless it is pushed faster.
 
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I have a 1-7" twist barrel and it just happens to shoot 50 gr. Nosler BT better than any other bullet I have tested. It should shoot heavier bullets better but my barrel just likes the 50 grainers. You might want to try a heavier bullet (40 grains may be a bit light for coyotes) but it will all come back to what shoots best in your rifle.
 
I've never found a faster twist barrel that will not shoot the lightweight bullets well. They seem to shoot all bullet weights well. Not saying the are optimum for all bullet weights, just saying they tend to shoot them accepatably well for hunting.

Just because a slow twist won't shoot the heavies, does not mean a fast twist won't shoot the lighter bullets......
 
You can load 75gr Hornady's to sammi length with no troubles.
You only have to worry about magazine clearance issues with the 80gr and up or the longer ogive's like vld's and some others...
1:7 twist should shoot stabilize just about anything.
 
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Originally Posted By: 2muchgunI've never found a faster twist barrel that will not shoot the lightweight bullets well. They seem to shoot all bullet weights well. Not saying the are optimum for all bullet weights, just saying they tend to shoot them accepatably well for hunting.

Just because a slow twist won't shoot the heavies, does not mean a fast twist won't shoot the lighter bullets......


As long as it is capable of stabilizing the bullet, Twist has nothing to do with accuracy. The only trouble may be that the lightest 40 and 50 grain bullets, especially the thinner jacketed varmint bullets ie dogtown, vmax etc. may come apart at higher velocities when shot from a faster twist BBL. They can tear themselves apart, I've seen it. You are correct. A 1-7 should shoot almost any weight bullet, and even the lighter ones can be slowed down to where they can be used fine. I think a 1-9 is probably optimal across the board unless there is a desire to shoot the heaviest bullets.

Personaly I have never loaded anything over 69gr in a .223/5.56 because If a heavier bullet is needed I reach for a bigger gun.YMMV
 
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