Thread: Twist Rate - is there a simple rule?

Hi everyone,
I have a new Sauer 202 XT in .223 which I bought for fallow and goats & walk around varminting (& for my son to shoot). The twist rate is 1:9.5(ish) and I imagined I would shoot around 65gr. Given that twist rate - is there a 'typical' projectile weight that will suit the barrel or is it still best to buy 4-6 different brands/weights/models and see which one groups best.
I'm not that precious with brands but do like Federal for my .204. Preferably I would like to find one brand and stick to it.
Thoughts or advice ? ... cheers PJ

I would try a few different projectiles in the weights you want. You may also find heavier projectiles will still shoot better with a slower than recommended twist. Got a pic of the rifle??

Originally Posted by Gunzrrr

Hi everyone,
I have a new Sauer 202 XT

Awesome rifle very jealous!

Have a play with this

http://www.bergerbullets.com/litz/TwistRuleAlt.php

Still pays to go shoot different bullets and see what works for real as opposed to the theory

I've got a spreadsheet set up with Greenhills formula, which is this:

Twist Rate = 150*(D/(L/D)) for velocities up to 2800 fps
Twist Rate = 180*(D/(L/D)) for velocities over 2800 fps
where D = bullet diameter in inches
L = bullet length in inches

A .223 69 grain Sierra Match king needs 10" or faster twist, so you should be quids in with a 65 grainer but, as has been suggested, you'll need to try a few variations before you find a pet load.

Originally Posted by R93

I would try a few different projectiles in the weights you want. You may also find heavier projectiles will still shoot better with a slower than recommended twist. Got a pic of the rifle??

Here it is ... thanks for the comments everyone !!
Cheers PJ

Was that through Sportsway?

Hey sako75
Yes it was from Sportways. I've bought a number of firearms over the years from a number of different outlets. Bill MacLeod, now from HF Botany shaped my thinking in terms of the way I "invest" in my gun rack. Given your Forum name, I'm pleased to say that one of my favourite rifles is my Sako .308 Bavarian. However, I stopped looking at anything Beretta/Sako when Beretta NZ trashed the price and therefore my perceived value of their products. By that I mean that I invested $3500 in an Xtrema that was only worth $1490 less than 6 months later. I won't make that "investment" mistake again. The other outlet I like is Staeger Sports (forgive my spelling if I have it wrong). Those guys have experience, talents, views, opinions, products, etc, and a fabulous attitude to customer service!
Each to their own eh? Isn't human behaviour fascinating ... cheers PJ

Have you got a better photo, mate? The one posted, for me, is small and hard to see.

The reason it's a small photo is its a crap photo so I resized it. For a fab photo I need a fox draped over the stock and a hot busty zombie chic in the background ... and maybe a glass of NZ made Pinot Noir somewhere.
I'll attempt to improve my photography skills and make another post. Maybe under the Varmint thread where I have my Ruger .17HMR and Kimber. Send me a private message and ill send you a bunch of photos.

JBM - Calculations - Stability have a play here as for your photo resizing try faststone photo resizer

Thanks Gunzrrr. I got my Sako there a few years back. Just about all my rifles I bought over the years came from there. Simon who works there just about sold me a Sauer when I was in there just to pass time while waiting to meet a customer down the road.
My first rifle was a 6.5x55 about 20yrs ago

super nice rifle i have a 202 Sauer Wolverine rifle in 223 beatiful rifles also in 30-06,25-06 and 6.5x68mm

Originally Posted by ishoot10s

I've got a spreadsheet set up with Greenhills formula, which is this:

Twist Rate = 150*(D/(L/D)) for velocities up to 2800 fps
Twist Rate = 180*(D/(L/D)) for velocities over 2800 fps
where D = bullet diameter in inches
L = bullet length in inches

A .223 69 grain Sierra Match king needs 10" or faster twist, so you should be quids in with a 65 grainer but, as has been suggested, you'll need to try a few variations before you find a pet load.

Considering this formula is over 150 years old and still perfectly valid for cup and core bullets it's obvious the poms knew a bucket load about ballistics before it was probably even a thing.