8" Twist in the 223

[K22]

I am told that in John Feamster's book, "Black Magic The Ultra Accurate AR-15" he reports that he shot a record 5 shot group at 200 yards of 0.0231 using 52 grain Sierra bullets in a 8" twist rifle. He goes on to state that he often recommends these lighter bullets since they tend to shoot more accurately even out of the faster twist rifles. (Info given to me by Greg at Tikkashooters.com)

I'm interest in this because I'm considering a Tikka T3 Lite in 223 which I can only purchase with an 8" twist and I want to shoot 50 and 55 grain bullets for varmint hunting.

So what do you guys think? This seems to contradict even the cartridge date section of this web site where in heavier bullets are recommended for this twist rate. A few of the newer reloading manual also recommend the heavier bullets.

 

[Klong]

I have shot 52 gr match bullets out of a 7 twist with good results. I think you can do this with a 223, if the velocity is not extreme. Keep it in the 2800 fps range,based upon my memory, and you should be fine. Keep in mind that some 12 twist will not shoot all of the light bullets well either, so you will need to see which bullets shoots the best.

 

[maxscm]

Years ago i had a Savage 12 Factory Bolt Gun, 9-Twist 223. It shot the heavies (69MK's and 80bergers) very small groups and would also shoot the 52MK's just a tight. I think spinning any bullet faster helps accuracy. But,,,i guess your not really going to know if they'll stabilize till you try em in Your rifle.
Another contradiction on twist,,In my AR a S&W M&P 223 cal. in a 9 Twist 16". It will shoot the 36 Barnes VG 3/4 moa and the heavy 69 or 77Mk's about 1-1.25 moa,,,,So Go Figure!

 

[MrMajestic]

From what I understand, rotational speed to just stabilize the projectile minimizes errors on centerline of it. No errors no problem! Of course you can spin them too much and they will come apart. I saw the results when shooting a 110 gr. V-Max out of a 10tw .300 H&H Ackley Magnum at an advertised 3900 fps! It is spectacular! ;D
Of course the higher rotational speed adds in fragmentation when the target is struck which can benefit a Varminter! Base line- Try it, good luck.

 

[Keith Glasscock]

It works great! I've shot varmints with 50 gr V-maxes out of a 7 twist at really sporty velocities (3200+). The bullets work really good, and the accuracy is everything you would need.

I wouldn't hesitate to recommend a fast twist 223 for varminting. They work good, and do a spectacular job on the animals - if you know what I mean...

My current varmint rifles are 223s with 12 twist and 9 twist barrels. You can't tell the difference in accuracy.

 

[markm87]

Agreed. Lighter bullets can shoot lights out in faster twist bbls.

 

[6.5 shooter]

My 8 twist bolt gun shoots 60 vmax into a single hole.
75hpbt also into a single hole but the 60's are just ontop of eachother.

 

[flatlander]

I agree with the general concensus that 8-twist bbls - which happens to be the minimum recommended twist rate for most 80gr bullets - will shoot the lighter bullets very well indeed. Only thing in my experience to avoid is trying to run any of the thin-jacketed varmint bullets full tilt in 8tw & faster bbls. I'm talking about Hornady SX, Speer TNT, etc. They were never intended to run really warm in fast-twist bbls, and most of the bullet makers warn against that practice - if not on the bullet box or a note inside, then in their respective loading manuals.

I blew up several bulk WW62PSPs out of a 1:7 Colt HBAR years ago, so I'd stay away from el cheapo bulk bullets in fast twist bbls. also.

 

[Laurie]

I'd agree with previous posts that lighter match bullets will usually perform well, sometimes exceptionally well, in 1-8" twist barrels. The reason for traditionally adopting the slowest twist barrel for best accuracy was the widespread incidence of imbalances in bullets, slightly asymmetric jackets and shapes etc that saw a high rotational speed increase their inbuilt tendency to veer off the aimed line. Today's mass produced varmint and match bullets are generally very well made and so a theoretically over-fast twist / rotation simply doesn't produce these problems. What it does mean is that poor quality 55gn FMJBT M193 pattern bullets will likely group even worse in a fast twist barrel than in a 1-12".

The 1-8" rate can see thin-jacketed lightweight bullets break up though, but it's not just a twist issue. I used to have a Lilja 1-8" match barrel on a .223R that would blow 52gn Hornady A-Maxes up, but only in hot weather and after the barrel got a bit fouled. The first 10 shots or so in a clean barrel were fine, then elevation went haywire for the next 5-10, then nearly every bullet exploded in a gray/black puff around 80-90yd downrange. Other people have shot this bullet in 8" twist barrels without any problems though.

Berger did a lot of work on exploding bullets before it introduced its thick jacket target models a few years back after complaints of the original (now 'Hunting') 6.5 and 7mm VLDs breaking up when fired at high MVs in fast twist barrels. It found all sorts of factors apply and the incidence is very barrel dimensions and condition plus fouling / ambient and barrel temperature specific making it impossible to predict when problems will arise.

So, all you can say about spinning 0.224" 50-55gn bullets 'too fast' in a .223 Rem is that it's usually OK, but good results can't be guaranteed for all makes / models of bullet in all barrels in all range conditions.

 

[K22]

Many thanks to all who responded - interesting post by Laurie especially the part about blowing up the 52 grain A max's.