Rifle Twist rates- .223

[danebrewer10 6]

Hi all, just a quick Q, am I right in thinking that you need a faster twist rate in a rifle to stabilise heavier bullets? so for bullets of 55-62gn say you'd want a twist of 1 in 8" and for lighter bullets from 40-55gn, you'd want 1 in 9"?

 

Cheers

DB

[bob.243 8,543]

I think the twist rates for the .223 are 1in9 and 1in12, your right the faster the twist rate the better it will handle the heavier bullet, 1in9 would handle the heavier bullets better than the 1in12.

 

ATB Bob.

Edited March 27, 2010 by bob.243

[sako trg 1]

I think the twist rates for the .223 are 1in9 and 1in12, your right the faster the twist rate the better it will handle the heavier bullet, 1in9 would handle the heavier bullets better than the 1in12.

 

ATB Bob.

yea thats my expirience 1 in 12 60gr max less than 1 in 10 heavier bullets.I think tikka did a T3 223 with a 1 in 8 twist but cant be sure.

[andyf 144]

Hi all, just a quick Q, am I right in thinking that you need a faster twist rate in a rifle to stabilise heavier bullets? so for bullets of 55-62gn say you'd want a twist of 1 in 8" and for lighter bullets from 40-55gn, you'd want 1 in 9"?

 

Cheers

DB

Just a point to consider.

A fast twist barrel (1 in 9) will stabilise heavier bullets, 60gr+, BUT it will spray 55gr and lighter all over the town.

You can't have it both ways, obviously if you could all .22 centrefires would be 1 in 9?

AndyF

[danebrewer10 6]

I think the twist rates for the .223 are 1in9 and 1in12, your right the faster the twist rate the better it will handle the heavier bullet, 1in9 would handle the heavier bullets better than the 1in12.

 

ATB Bob.

 

Oh I wasn't aware of the 1 in 12 twist- I guess that's more for varmint shooters with 40gn bullets... the 1 in 8" twist is an offering in most AR straight pull rifles in the stainless H-BAR barrel, the 1 in 9" seems to be the chromo steel barrels...

 

then I think Nosler do a 60gn balistic tip and a 60gn partition.....nice.....

[Deker 3,478]

The Tikka T3 is available in 1-8 and 1-12, mine is the 1-8.

 

It handles everything from 40-75g well, I don't know why but it does.

 

Tried a selection about a year or so back at Bisley 200 yard Short Siberia. The groups were all pretty tight and all in a nice straight line up and down.

 

I was very happy, but it does seem that all my centrefires shoot pretty well, even when you feed them the cheap stuff!!

[RicW 67]

As said, a faster twist rate will stabilise longer (it's the length that matters ducky!) ie heavier bullets better. Where you may have a problem is with thin-jacketed light (short) fragmenting bullets at high MV. If they are spinning too fast they can break up in flight due to excassive centrifugal force. It is very unlikely to be a problem with factory ammo but if you go for hot handloads you may have a problem.

 

Ric

[JonathanL 4]

As said, a faster twist rate will stabilise longer (it's the length that matters ducky!) ie heavier bullets better. Where you may have a problem is with thin-jacketed light (short) fragmenting bullets at high MV. If they are spinning too fast they can break up in flight due to excassive centrifugal force. It is very unlikely to be a problem with factory ammo but if you go for hot handloads you may have a problem.

 

Ric

 

I've done that with 75grn bullets from a .257 Weatherby. Think I got 1 or 2 bullets to the target out of 25. The rest disappeared in a little puff og grey coloured mist.

 

J.

[Blakloks 5]

what the hell is twist rate??

[RicW 67]

If the rifling completes one turn in, say, 10", that is described in British or American terms as "1-in 10". It defines the rate of turn of the bullet in the barrel. Most sporting rifles use a twist rate of around "1-in 12". Basically, the twist rate affects how fast the bullet is spinning whan it leaves the barrel. A longer round requires a faster spin in flight to maintain ballistic stability, but a twist rate that is too high can cause lighter, ie shorter, bullets to break up in flight due to excessive centrifugal force. Long range target rifles tend to fire long heavy bullets which need the fast twist rate for down-range stability. It comes down to what bullets you are using. Sporting rounds tend to be lighter, but are expanding/fragmenting on impact. Target rounds are longer, thinner, and require fast twist rates.

 

Now I'm gonna put my head down while I get shot at.

 

Ric

[Blakloks 5]

has evey rifle like a 222 or a 223 got diferent rates?? My mates use 50gr ballistic tips for foxes dont know what the twist rate would be? I aint got a rifle yet im just looking into it and this has pickled my head

[RicW 67]

If you are field shooting then buy the gun you like the look or feel of. It's only if you are really concerned about down range accuracy that twist rate starts to matter. Then try all the factory rounds you can lay hands on, see which works best, and use that as base for handloads.

 

ATB

 

Ric

[jamie g 17]

has evey rifle like a 222 or a 223 got diferent rates?? My mates use 50gr ballistic tips for foxes dont know what the twist rate would be? I aint got a rifle yet im just looking into it and this has pickled my head

 

im guessing most 222 rifles are a 1 in 14 like most 22/250.

 

223 you can get

1 in 12

1 in 9

1 in 8

[danw 1,748]

has evey rifle like a 222 or a 223 got diferent rates?? My mates use 50gr ballistic tips for foxes dont know what the twist rate would be? I aint got a rifle yet im just looking into it and this has pickled my head

 

im guessing most 222 rifles are a 1 in 14 like most 22/250.

 

223 you can get

1 in 12

1 in 9

1 in 8

 

My sako varmint .222 is 1 in 14

[danebrewer10 6]

has evey rifle like a 222 or a 223 got diferent rates?? My mates use 50gr ballistic tips for foxes dont know what the twist rate would be? I aint got a rifle yet im just looking into it and this has pickled my head

you can easily measure the twist rate of a rifle, just push a jag with a patch on it down the bore so that it turns with the rifling, then take a piece of tape and fold it round the rod near the handle so that it is facing upwards. put a mark on the rod either with a pen or a piece of tape then push the patch down the bore, when the tape has made a full rotation, put another mark on the rod at the datum point you chose for the first mark then measure the distance between the two marks...

 

so going on the content of this thread, you mates rifle'll probably be a 1 in 12" I'm just guessing here