Which twist rate

Essex stalker

Well-Known Member
Got my variation through today with a slot on it for a .223 which I'm going to use with NV for foxing. Already got a couple of SAKO 85 in other calibres which I'm very happy with so planning to get another 85 but in .223. Unfortunately SAKO don't appear to do the the .223 in the synthetic / stainless so will probably go for the laminate / stainless.
This is offered in two twist rates either the 1 in 8 or 1 in 12. As its mainly for foxing I will probably be using a fairly light round, ie 40 to 50 grain, just wondered if anyone had any experience of this and which twist rate they would go for.

With regards to the NV, it will either be a the new pulsar 970 (already have a 870 on a .22 for rabbits which I like because of the range finder) or a Drone pro, advice willingly taken.
 
Drone Pro and 1 in 12 twist.
1 in 12 because for NV foxing you want as flat a trajectory as possible making range judgement is less critical.
1 in 12 handles the lighter, faster bullets better than 1 in 8.

Cheers

Bruce
 
1 in 8 will do 40s plus a few more ,may prefer 55s and up but in the future newer bullets might be the norm as it states in another simular thread below left ,,;)
 
Either twist rate will do to be honest, my 22/250 wears a 1:8 and shoots 55g blitzing really well. The drone 10x is fantastic too!
 
I have a sako 85 laminated stainless varmint barrel. 223 with a 1 in 12 twist and shoot 50 grain v max home loads I use mine for mainly daylight shooting and am very happy with accuracy and consistency.
You won't go wrong with a 1 in 12 twist rate on light bullets mine also shoots 60 grain bullets well.
 
My Remington 700 has a 1-12 twist, when shooting military ammo the bullets go though the target sideways at 45yds. I use Hornady 50gr V- max for faxing and have shot rabbits out to 400yds with them.
 
This one is simple regarding twist, bigger bullets = more twist rate i.e 1 in 8. Bigger bullets for longer range shots but have more of drop to understand.

I would stick with the 1 in 12 if the foxes aren't long range!
 
Get the 1-8" you can use anything from 45gr to 80gr bullets, if you get the 12" twist you are limited to 60gr flat base at best. Resale will also be better with the 8 twist should you ever sell it too. Why buy a Ferrari and only drive it at 30mph ?
 
The arguments pushing for 1:8 ignore the fact that the OP's use for the rifle is foxing at night. The longest shot I take at night is 300 metres. (I realise there are guys out there with better eyes who take longer night-time shots!).

I would suggest that 40gr VMax are the way to go. I own a Sako 85 Varmint Laminate Stainless and it has had about 2000 rounds through it. The vast majority have been Norma 40gr Vmax factory, although it does shoot Winchester Silver Tip 55gr very well too. It seems that the Sako/Tikka 1:12 barrels really like the 40gr Vmax and great results can be had using Norma or Hornady factory ammunition. In fact, the results are so good, I've never felt the need to homeload the rounds.
 
Twist rate is an interesting one. It's not true that a 1/12 is better per-se than a 1/8 at shooting lighter bullets. The 1/8 will stabilise lighter bullets at lower MVs than slower twist rates whereas the slower twist rate wont be able to stabilise heavier bullets. The differences in terminal velocities between the two twist rates is only of marginal interest w.r.t.trajectories at 200 to 300 yds. There's nothing much in it. I've used both 1/12 and now 1/8 twist rates and by far prefer the flexibility that the 1/8 allows.

However, what bullets a faster twist rate barrel can handle is also dependant upon the bullet construction itself. A main consideration in faster barrels is the bullet RPM and specifically the centrifugal forces this places on the bullets. Very thin walled jacketed bullets can disintegrate before they leave the barrel if spun too quickly, but there are plenty of lighter bullets that can be spun up very rapidly in faster twists, even with MVs of around 3,600-3,700fps.

All you can say is that unless you've tried a few different bullets, there's more risk of some very lightweight bullets coming apart if driven hard in faster twists. This article explains it very well:

http://www.accurateshooter.com/technical-articles/calculating-bullet-rpm-spin-rates-stability/

I can happily shoot 50gr Vmax in my 1/8 at close on 3500 fps with no issues on stability. I tend to use the heavier bullets for their better BC though and shoot at up to 300 yds with the flat base 60gr Vmax which seems to shoot better groups the faster its pushed (3200 fps produces very accurate groups in mine).
 
My new barrel on the 223 shoots 52 grain through 75 grain bullets into touching groups - It is a 1 in 8 twist.
Best of both worlds - 1 in 8 can do more than 1 in 12 so it makes sense to me (but I don't use NV & know my bullet drops)

Ian
 
The most accurate factory 223 in my house is a 1-10" Tikka. I would search for one of those if I had the time. Otherwise, I have 1-14, 1-12, and 1-8 twists. My latest play thing is a Ruger American Ranch with a 16.5" 1-8 twist tube tucked into a MDT Chassis. I shoot bullets from 50 to 77 grains with superb accuracy and i match the bullet to the activity: 50 or 55 grain Noslers BTs for prairiedogs and 69 grain Custom Competition for long range play. I've not shot 40 grain from this rifle but I'm sure it would shoot them well at reasonable speeds.~Muir
 
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