8,5 or 10. That is the question.

[Andrev]

Hi Guys, need your help please.
I am in the process of buying the equipment for building a 6 XC. I have access to Bartlein 4 groove barrels in 8,5 or 10 twist. I will be shooting minimum 87 gr HDY, 88 gr Bergers and maximum 95 gr SMK or Bergers.
The discipline is a simulation of hunting conditions with a mixture of short range,50-80 meters) offhand shooting and longer range,350 meters max) life size animal paper targets and 8" steel swingers.
Distances are unknown, positions are varied and the wind is unknown.
I think the 87 to 95 grainers will provide a good trajectory and be able to buck the wind.
The twist rate question is driving me up the wall however.
Any advice?
What kind of speed can I expect with the XC?
Greetings from sunny South Africa.

 

[HPMike800]

If it were me I would pick the 1:8.5 twist barrel. 1:10 is on the edge for 90-95's per Bergers website. You may very well end up shooting 105-107's in the rifle as the 6XC shoots them very well. Just my $0.02.

Mike

 

[Andrev]

Thanks Mike,
I will probably not go above 95 gr to try to limit recoil. The discipline requires shooting from sometimes very uncomfortable positions with limited time and recoil can become an issue.

Andre

 

[expiper]

There is no reason to feel like you have to "limit" your choice to 8.5 or 10 Just because you can shoot 107's doesnt mean you have to...but it is nice to be able to if YOU ever change ur mind....in this day and age you can call Bruno and get an 8 twist in the mail in a cupla days....dont let anybody force you to use the bbls. they have layin around....they culdnt sell em to anyone else either....get what you want and what you want is what will work for you....the majority of good shooting BR's-Dashers-etc are 8' twist.....the records speak for themselves...Roger

 

[fdshuster]

When in doubt, go with the faster twist: it's a lot more versatile.

 

[Andrev]

Thanks guys, I will go with the 8,5 twist.
Unfortunately it is not possible for us in South Africa to change barrels easily. It involves waiting months for a barrel due to very stringent,read ridiculous) permit requirements for the dealers, and then more months to apply for a barrel change from the local government. A local dealer has now been waiting 8 months for an import permit after buying barrels! The cost of financing this is also becoming an issue. This bureaucratic nonsense has caused a lot of guys to give up shooting.
I am lucky to be able to have a choice between 2 twists on a good quality barrel.

Keep shooting!
Andre

 

[HPMike800]

That's what I thought. The 8.5 will work very well, get it before it's gone!

Ya know; If barrels are that hard to get I would seriously think about going 6BR instead of 6XC. You get double the barrel life and can still push 95's around 3,000fps. This is assuming your sport is single load/single shot.
Mike

 

[Andrev]

Thanks Mike,
I planned to use the XC to launch the 95 grainers at 3100 fps.
The rifle will be single shot built on a Musgrave RSA target rifle action designed for the 308 round. As a novice in this regard, I was not aware of barrel life problems with the XC. The 243 Win calibre rifles are doing the best in our competitions and the XC seems to be a step up as far as barrel life is concerned.
Will the 6 BR be able to get the speed easily?

Andre