.243 Twist

stevenedwards

Well-Known Member
Gentlemen what is considered the ideal twist rate for a 243. Most seem to be 1 in 10 off the shelf but comment here suggests that is not the best for the heavier end of the range, 90 to 100 g . Is this correct and would a faster twist be more versatile, say 1 in 8.
What experience do you have particularly anyone who has had a rifle "built"

Many thanks

Im not constrained by barrel length, 600mm min.
 
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takbok

Well-Known Member
There's no harm in going 1:8 if you're going to be using around 100gr bullets.

I've just had my 6x45 built with a 1:8 barrel and it's shooting 105gr amax well.
 

nun_hunter

Well-Known Member
If you can go 1:8 as it opens up all the high BC bullets to you. You should still be OK with a flat Base soft point at 100-105 grains with a 1:10 but you'll struggle with the long high BC bullets.
 

jcampbellsmith

Well-Known Member
Gentlemen what is considered the ideal twist rate for a 243. Most seem to be 1 in 10 off the shelf but comment here suggests that is not the best for the heavier end of the range, 90 to 100 g . Is this correct and would a faster twist be more versatile, say 1 in 8.
What experience do you have particularly anyone who has had a rifle "built"

Many thanks

Im not constrained by barrel length, 600mm min.
I re-barrelled my 243 Win Sako 75 from 1:10 to 1:8 in order to shoot 105 A-Max/107 SMKs. I also had my 6XC built with 1:8 twist. Regards JCS
 

NigelM

Well-Known Member
As has been said, 100g flat base will work, 100g boat tails unlikely to. Mine will shoot 100g ProHunter very well but doesn't like the 100g GameKing.
 

20-250

Well-Known Member
There's no harm in going 1:8 if you're going to be using around 100gr bullets.
Don't make the mistake of assuming that a 1 in 8 twist 6mm barrel will only shoot heavy for calibre bullets. My 1 in 8 .243 shoots 70 grain bullets really well.
 

minikeeper

Well-Known Member
Don't make the mistake of assuming that a 1 in 8 twist 6mm barrel will only shoot heavy for calibre bullets. My 1 in 8 .243 shoots 70 grain bullets really well.
and mine shoots 55gr well. The only downside is an increase in spin drift, but that is academic and not a real world problem.
 

stevenedwards

Well-Known Member
As usual lots of help. It seems that 1in 8 will get me from 75 to 100g which is ideal but 1 1n 9 looks interesting. I don't know if that is on offer.
 

takbok

Well-Known Member
Don't make the mistake of assuming that a 1 in 8 twist 6mm barrel will only shoot heavy for calibre bullets. My 1 in 8 .243 shoots 70 grain bullets really well.
Of course it will shoot light bullets well. I have 70gr blitzkings and 62gr GSC'S that Im going to be mainly using.
 
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EDCM

Well-Known Member
It all depends on what you are using the rifle for. If any range work over 600yds go for the faster twist rate.. but you will be limited in "off the shelf" choice of rifle.

I have a Browning x-bolt varmint 1-10 that will not shoot Amax 105s but will shoot the 100gr Gamekings. its all down to bullet length.

Eddie
 

Highlandsjohn

Well-Known Member
It all depends on what you are using the rifle for. If any range work over 600yds go for the faster twist rate.. but you will be limited in "off the shelf" choice of rifle.

I have a Browning x-bolt varmint 1-10 that will not shoot Amax 105s but will shoot the 100gr Gamekings. its all down to bullet length.

Eddie
This malarkey about '100 grn bullets won't shoot accurately in a 1-10.'comes from.

Chinese whispers, laziness to work at developing a load, not experimenting with established and proven factory ammunition. Not aware of rifle's anomalies, or folk who just cannot tell one end of a round from the other..(Topical)

The .243 1-10 no doubt prefers a 70-90grn bullet. If that is all you need great there are multiple choices to pick from. But that does not equate with it wont shoot 100grn accurately.

These 'trends' usually emanate from the manufacturers bottom line then the rumour mill takes over.
 

EDCM

Well-Known Member
I'm not sure if the above was directed at me. But I did say "but will shoot the 100gr Gamekings."

I have used the Gamekings to 900 yds with reasonable accuracy at Orion.

If anyone knows of a bullet with a better BC that a 1 in 10 will shoot​ Please let me know.

Eddie
 

Highlandsjohn

Well-Known Member
I'm not sure if the above was directed at me. But I did say "but will shoot the 100gr Gamekings."

I have used the Gamekings to 900 yds with reasonable accuracy at Orion.

If anyone knows of a bullet with a better BC that a 1 in 10 will shoot​ Please let me know.

Eddie
No Eddie we are on the same page.:thumb:
 

dodgyknees

Well-Known Member
As has been said, 100g flat base will work, 100g boat tails unlikely to. Mine will shoot 100g ProHunter very well but doesn't like the 100g GameKing.
Ditto

i like the range of projectiles the 1:10 allows me. It gives me great flexibility in the field to take anything from hares to red hinds without being too under- or over-gunned. Here its all longer range open country stuff where we've got heaps of time to choose what to shoot cos often theres 3 or 4 target species on a single face... I carry 3 weights, its zeroed for the 100gn pill but only requires a few clicks to adjust for the lighter pills which I find easier than trying to remember the additional holdover.

My 1:10 20" barrel Howa with dpt suppressor shoots 100gn Prohunters into 40mm groups at 300m. It took a while to work out the load and plenty of fine tuning of c.o.a.l. No exaggeration, no scoffs of derision pls. But it doesnt like the boat tailed Gameking.

This rifle has now taken over longer range fallow and red hind / yearling meat kills from the T3 .308 primarily because the T3 isn't suppressed.

The 1:10 also excels with 75gn VMax (goats) and 58gn Barnes varmintors (hares). Was shooting hares up the Ahuriri last week on a beaut windless evening at 300-400m and the .243 1:10 shooting 58s was as accurate as the .223 T3 Supervarmint 1:12 shooting 55gn Blitzkings. Photos posted shortly in photos section.
 

NigelM

Well-Known Member
Ditto

i like the range of projectiles the 1:10 allows me. It gives me great flexibility in the field to take anything from hares to red hinds without being too under- or over-gunned. Here its all longer range open country stuff where we've got heaps of time to choose what to shoot cos often theres 3 or 4 target species on a single face... I carry 3 weights, its zeroed for the 100gn pill but only requires a few clicks to adjust for the lighter pills which I find easier than trying to remember the additional holdover.

My 1:10 20" barrel Howa with dpt suppressor shoots 100gn Prohunters into 40mm groups at 300m. It took a while to work out the load and plenty of fine tuning of c.o.a.l. No exaggeration, no scoffs of derision pls. But it doesnt like the boat tailed Gameking.

This rifle has now taken over longer range fallow and red hind / yearling meat kills from the T3 .308 primarily because the T3 isn't suppressed.

The 1:10 also excels with 75gn VMax (goats) and 58gn Barnes varmintors (hares). Was shooting hares up the Ahuriri last week on a beaut windless evening at 300-400m and the .243 1:10 shooting 58s was as accurate as the .223 T3 Supervarmint 1:12 shooting 55gn Blitzkings. Photos posted shortly in photos section.
Just as a matter of interest, what jump did your 100 Prohunter like to the lands?
 

NigelM

Well-Known Member
This malarkey about '100 grn bullets won't shoot accurately in a 1-10.'comes from.

Chinese whispers, laziness to work at developing a load, not experimenting with established and proven factory ammunition. Not aware of rifle's anomalies, or folk who just cannot tell one end of a round from the other..(Topical)

The .243 1-10 no doubt prefers a 70-90grn bullet. If that is all you need great there are multiple choices to pick from. But that does not equate with it wont shoot 100grn accurately.

These 'trends' usually emanate from the manufacturers bottom line then the rumour mill takes over.
I'm sorry, but the physics say you're wrong. Why do you think the bullet manufactures recommend minimum twist rates for their bullets. Look at any stability calculator and it will tell you pretty clearly what bullet is likely to work and what will not in your gun dependant upon your twist rate, bullet weight, length and speed. The physics is a much more reliable place to start any load development than opinions from the internet.
 

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