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6.5x47 lapua recommended twist

Hi,
I need some help.
What is the recommended twist rate for the new 6.5x47Lapua.
I intend to shoot the 123 and 139 scenars from a Krieger barrel.I do not yet know the velocities .Any advice on the above would be appreciated.

Regards
Bobby
 
For the 139's I would use a 1:8.5" twist. With a lot of 6.5 x 284 shooters a 1:8.5" twist Krieger is the barrel of choice. 1:9" twist can sometimes be marginal with bullets in the 139-142 gr range.

Robert Whitley
 
I would go with an 8 twist if you want to shoot the 139s and 140s. I think "reliably achievable" max velocities for the 140s are 2830 fps, and 3000-3050 with the 123s.

Lapua lists a max velocity for the 6.5x47 shooting 139s as 2723 fps. Our tester, Darrell Jones was able to push them up near 2900, but that might not be possible in all barrels. Lapua also recommends an 8-twist for the 123 Scenars, but an 8.5 would work with them--maybe even a 9=twist. But I don't know anyone who has tested a 9-twist with the 120s to make sure.
 
Hopefully, my 6.5 barrel will be rechambered to 6.5x47 within the next three weeks and back to me. It is a 30" 8 twist Krieger, and will be going on my Speedy F-Class rig.

My intentions are to shoot this with the new 130 Berger VLDs...

I have already shot some of the prototype 130 Bergers with this barrel, but out of the current chambering - the Grendel. They shot extreamly well at 300 yards, and I am looking forward to the extra boiler room and moving back to the 600 yard line.
 
I would agree with the 8 twist and think 8.5 would be marginal for the 140gn, particularly in cold low altitude locations. I'm wondering if anyone does a tighter twist,e.g. 7) in 6.5mm.

Alan
 
My experience in non-benchrest applications with the 6.5-08/260 Rem and smaller cartridges has been that there is no real penalty for using an 8 twist barrel with a 120 gr MK or 123 gr Scenar as compared to a 9 twist barrel. The nine twist barrel is probably closer to "optimal" for the 120 gr class of bullets but the 8 twist will allow the use of heavier bullets in the expected attainable velocity range of the 6.5x47 Lapua. Boots Obermeyer has shot a number of 8.6 twist barrels with a variety of bullets with good results,the trigger operator has something to do with this), but the barrel has done its job as well.

If the 123 gr bullet is the heaviest that you intend to use the 8.5 twist or 9 twist just might be the way to go. The problem is that the barrel must actually be the advertised twist. One individual with whom I exchanged information had used 10 twist barrels with good results with a 107/8 gr class bullet, but there were manufacturing changes to the bullet,it became longer and less consistent) and his barrel would no longer shoot them well. The pics,and measurements) of the changes in the bullets were obvious, but "did not seem that big" which led me to believe that the 10 twist barrel had been right on the edge in the first place. Frankly it had never occurred to me to use a 10 twist barrel as none of the computer programs had suggested it as being a useful choice.

As with any of these things, seemingly small or insignificant differences may cause substantial changes in the result when dealing with barrels...in other words your mileage may vary.

Let us know what you decide and how it works out.

Cheers
 

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