Barrel twists

[CodeBasher]

Regarding barrel twist,

In my shopping for an F-Class 223 for wife and kidlet, I've learned that the usual factory 1/10 to 1/12 twist is rubbish for long range accuracy. To have a chance at hitting something then 1/7 to 1/8 twists are the way to go.

Ok that's fine, why almost all manufacturers just don't go with the tighter twist straight up I'll never know. But moving on....

Now the 308. My F-Class Barnard has a 1/13 twist but usual factory 308's have a 1/10 twist. So far I've figured out that the tight factory twist is designed for use by heavy 210+grain Godzilla stopping bullets.

Now for my questions.

1) [308] Can I assume the tight twist big 210+grain bullets are just too heavy for a 308 charge to throw 1000 yds where the 155 grain ones aren't.

2) [223] Can I assume an ultra light bullet to allow a 1/12 twist barrel to be accurate would be so light that at long range it's just too light to stay supersonic. Or at the very least an insect fart as the round goes by would add the proverbial 20 minutes of unexpected wind-age.

ta and thanks

[johnk]

No, you should consider what the uses for a standard sporting rifle in the two calibres are.

The .308 can be expected to be used with animal stoppers around 175 grain for open country & 200 to 220 grain round nose pills in the scrub. The 1:10 twist can handle those elegantly & can do a reasonable job with 130-150 grainers for those who want a lightweight varmiting pill.

The .223 is considered a varmiter by & large & so is set up for the projectiles around 55 grain that suit that purpose. Sometimes they'll run up to 63 grains & (seldom) 69.

As far as usage goes, my match rifle loves 10 twist when it's slinging 208 Amaxes or 210 Sierras or Bergers, but that & gawdelpumiftheydo F Open are the only classes with access to the big ones. The rules for FS & TR are for 155 only.

The final piece of the equation is that we aren't usually consumers of factory rifles - most of ours are custom builds - so the market doesn't generally recognise our needs (except maybe Savage occasionally).

John

[CodeBasher]

"The rules for FS & TR are for 155 only"

Ah! that explains my 308 dilemma!

[10FPAT]

[quote="CodeBasher"]"The rules for FS & TR are for 155 only"

Ah! that explains my 308 dilemma! [/quote]

That applies to F Standard as shot here in Oz, but if you shoot offshore you can use any bullet weight in F T/R (Standard) competition.

My 1 in 10 Savage barrel shoots Dyer & Sierra 155's very nicely!

[Chris Burdett]

my 1:10 shoots 155gn,s good enuf for the club champs if you stuff 47+ 2208 in it, and BTW the old forgotten 200gn. SMK still shoots good enuf to win.

[Barry T]

Hello ,thats right there is nothing wrong having a 1 in 10 twist.i also have a savage rifle and shoot in the f class standard.
i use 155 nosler competion projectiles with no problems,i use 47 grains of ar2008 in a remington case and cci large primer.my o.a.l is 73.1 mm. cant get those dyer's to shoot ,but would like them tooo .would like to know load and lenght please for a savage 1 in 10 twist rifle. from barry t

[10FPAT]

[quote="Barry T"]Hello ,thats right there is nothing wrong having a 1 in 10 twist.i also have a savage rifle and shoot in the f class standard.
i use 155 nosler competion projectiles with no problems,i use 47 grains of ar2008 in a remington case and cci large primer.my o.a.l is 73.1 mm. cant get those dyer's to shoot ,but would like them tooo .would like to know load and lenght please for a savage 1 in 10 twist rifle. from barry t [/quote]

G'day Barry,
I'm using 46grns of 2206H with the Dyers seated at around 72mm & they shoot sub MOA from my 24" 10FP Savage at around 2930 fps, Lapua cases & CCI primers.

Rgds Bill

[M12LRPV]

As mentioned, in 223 savage do 1 in 7's

Sako and Tikka also do 1 in 8's.

[CodeBasher]

As mentioned, in 223 savage do 1 in 7's
.

I spoke to a Savage Australian sales rep and asked him

"I'd dearly love a Model 110 BA chambered to 223, 7.5 barrel twist with removable muzzle brake. That would be truly be the rifle for all occasions, F-Class standard, hunting, siluette shooting and perfect for wife and son usage due to the 223 low recoil. "

His response was, "you can have anything you want if you have the money.

[Monty Burns finger tap... "Excellent!!!"]

[M12LRPV]

As mentioned, in 223 savage do 1 in 7's
.

I spoke to a Savage Australian sales rep and asked him

"I'd dearly love a Model 110 BA chambered to 223, 7.5 barrel twist with removable muzzle brake. That would be truly be the rifle for all occasions, F-Class standard, hunting, siluette shooting and perfect for wife and son usage due to the 223 low recoil. "

His response was, "you can have anything you want if you have the money.

[Monty Burns finger tap... "Excellent!!!"]

Muzzle brake on a 15lb 223

It'll kick like a 22lr. (my f-class setup does)

I think you'll be right without the brake Sure would look the goods though

[CodeBasher]

Ya GOTTA have the looks.