8 twist tika 223

[chopperjase]

hi all

 

an RFD that ive recently spoke to has told me he can aquire an 8 twist 223 t3 in any format of barrel choice normal or varmint.and short waiting time .

my question is would a tight twist t3 223 be desirable as a fox / odd range day tool ,as remington/ police type 223 tight twist are impossible at moment to obtain .

is it me or are tight twist 223 s becoming more popular as 224 bullets are evolving and becoming heavier with higher BCs .

 

if you were in the market for a 223 varmint rig /odd range day would you go 1 in 8 or 1 in 12 twist.

 

thanks all

[dannywayoflife]

Ive recently sold my tikka t3 1in8 and they are far more flexible in my mind than a 12 twist.

[MrCetrizine]

I'd go for a 1:8 and did. Purely so you can throw a 77gn Berger through it. Those things are stupidly accurate for as far as a .233 can shoot.

[baldie]

I only ever buy stock barrels in in 8 twists.

 

Anything else is a special order. I think i,ve probarbly 10 in at the moment. An eight will shoot anything from 55 grains upwards.

[204 rem]

I have a 1/8 twist barrel.That shoots 60gr vmax and 75gr amax spot on.and I am well pleased with it So I would go with the 1/8 mate.

[pengo]

I'd go for a 1:8 and did. Purely so you can throw a 77gn Berger through it. Those things are stupidly accurate for as far as a .233 can shoot.

Hi there,

 

Quite interested to hear what you use to achieve such good results?

 

Cheers. Paul

[MrCetrizine]

Hi there,

 

Quite interested to hear what you use to achieve such good results?

 

Cheers. Paul

CCI BR4 igniting 24.2gn of N140 which pushes a 77gn Berger Target BT out of Lapua brass and through a Tikka T3 with a 24" 1:8 heavy barrel, aimed through a Swarovski Z6i 5-30x50.

[247sniper]

A .223 shooting shooting 75 grain AMax's will have similar if not better ballistic out to 600 yards and not much in it out to 1000 yards. Basically shooting similar if not high BC bullets at slightly higher speeds.

[gbal]

Hmmm...I wonder if BC alone is the only/best criterion.Of course a higher Bc is desireable,but BCs are not just G1 or G7 (you will be pleased/distraught to find there are G2,3...6 too-each for a somewhat different bullet shape-and bullets increasingly do differ-tangent/secant /hybrid etc,thoug G1 is a poor representation usually.) But BC is not a constant,and varies a bit with velocity-basically what the

transonic/subsonic issue is about,when we get closer to 1000y....

i7 may be a better coefficient-against a standard (for the G) of 1.00,a higher value is more drag,less efficient,a lower value is 'better'.

This helps explain why most 168 30 caliber bullets are great to about 600y,but fare much less well at 1000y.The 155g palma is a bit over at 1.092,and the 155.5 hybrid is well under at .945,so we would expect better long range performance from the hybrid.

 

So we can ask-does all this apply to 223 bullets-any small differences in BC/velocity (75 and 77 g ) might not show below say 600y,but given the envelope for any 223 is stretching by 800/1000y,any such differences might be more apparent....they might (all) get 'there'....but 'there' is likely to be a rather larger bit of real estate for some.....:-)

 

Gbal

[MrCetrizine]

I think the reason that Berger 77s shoot so well in my rifle and AMax 75s shoot so badly is down to the Bergers having a tangent ogive instead of the AMax's secant ogive.

 

The Bergers are much less fussy about seating depth and always enter the rifling well which means they exit the muzzle well too.

 

I can also get 69gn SMK with secant ogive to shoot well but I have to nail the seating depth to within 2 thou or the group opens up.

[gbal]

I think the reason that Berger 77s shoot so well in my rifle and AMax 75s shoot so badly is down to the Bergers having a tangent ogive instead of the AMax's secant ogive.

The Bergers are much less fussy about seating depth and always enter the rifling well which means they exit the muzzle well too.

I can also get 69gn SMK with secant ogive to shoot well but I have to nail the seating depth to within 2 thou or the group opens up.

Yes,that's why Berger developed the hybrids-a compromise tangent/secant that just works-almost all the ballistic advantage,much more tolerant of seating depths. So a 224 hybrid should do well.

 

(how do you measure how well any bullet enters the rifling,or exits the muzzle ? I don't doubt it's a factor,but how do you know-concentricity-as one possible indicator-won't distinguish ogives.)

Do A max shoot poorly generally-just bought some to try,and join this '223 spot on at distance' club!

Gbal

[MrCetrizine]

I can't actually measure how well the bullets are running through the barrel, it's more of an observational best guess. The Bergers group well no matter what seating depth is used but bullets with secant ogives only group well with a very specific depth. As the bullet can't really alter much while in the rifling, I just assume that the tangent ogive bullets must be entering in a better way as the difference is noticeable even at very short ranges.

 

My rifle has never liked AMax, they don't shoot badly by most standards but SMK, Bergers and even Hornady Match, shoot much better.

[gbal]

I can't actually measure how well the bullets are running through the barrel, it's more of an observational best guess. The Bergers group well no matter what seating depth is used but bullets with secant ogives only group well with a very specific depth. As the bullet can't really alter much while in the rifling, I just assume that the tangent ogive bullets must be entering in a better way as the difference is noticeable even at very short ranges.

My rifle has never liked AMax, they don't shoot badly by most standards but SMK, Bergers and even Hornady Match, shoot much better.

Thanks,Mr C. From what you say,these Bergers (clearly not VLDs) are seating depth tolerant,and perform very well,at most/all seating depths.

You found the 75 AMax (secant ogive) are very depth fussy- and they only grouped well at one seating depth;so was that best grouping comparable to the Bergers? I'm trying to find whether the Amax are a fiddle,but can be as good,or whether even at their their optimum seating depth, they are still significantly poorer than the Bergers

 

Have others found this,especially at longer ranges-500y+?

 

Gbal

[MrCetrizine]

AMax never grouped well in my rifle. They do very well in others but mine always hated them. I have a friend who shoots AMax through the same hole at 300m but that's from a 1:12 .223. For me, 75gn Hornady match grouped as well as Bergers, which I find odd as I thought they were almost identical to AMax except the polymer tip. They needed a near Max load and seating into the lands to do it which was OK as there were no pressure issues. 69gn SMK group as well as Bergers but need perfect seating to do it or I get occasional flyers which again is OK as I don't mind seating each one perfectly.

[gbal]

AMax never grouped well in my rifle. They do very well in others but mine always hated them. I have a friend who shoots AMax through the same hole at 300m but that's from a 1:12 .223. For me, 75gn Hornady match grouped as well as Bergers, which I find odd as I thought they were almost identical to AMax except the polymer tip. They needed a near Max load and seating into the lands to do it which was OK as there were no pressure issues. 69gn SMK group as well as Bergers but need perfect seating to do it or I get occasional flyers which again is OK as I don't mind seating each one perfectly.

OK,one last question-does 'seated perfectly' mean to the exact depth each time (which good dies should ensure) or zero concentricity run out as well (good dies and very good case prep)?

Gbal

[MrCetrizine]

Just exact depth, I've never checked concentricity.

[gbal]

Just exact depth, I've never checked concentricity.

Thanks for all this-as usual it's try and see for each rifle,but at least I can be prepared for some depth fiddling,or use Berger(hybrids)!

Gbal

[pengo]

Thank you for the information MrC.

 

I think I might try to emulate this with my rifle (Tikka T3 Sporter 1:8 heavy barrel), although I haven't been shooting HV rifles for long and certainly not above 100 yards yet, as I'm trying to sort out a decent load, hence the gratitude for your response.

 

Also, I wasn't aware that it could be used to shoot out to 600 AND 1,000 yards, potentially. Now that really would be something on my "must do" list.

 

Thanks for everything.

 

Cheers. Paul