6.5mm 1-8 or 1-9 twists

[Visionz45]

Ive recently noticed some hype in twist rates for 6.5mm bullets. Im shooting a 264 win mag with a 1-9 twist. I shoot mostly 140 nosler partitions though would like to try 130's and maybe some 160's for fun. If I were to switch to a 1-8 what would I expect, changes in velocity/pressure, especially with my 140's I curently use? Secondly is there any reason to opt with a 3 groove barrel over a 6 groove?

 

[Bobarino]

in my opinion, there wouldn't be enough of a difference in performance of any kind ot justify the expense of switching to a 1:8 or a 3 groove barrel. i do believe that a 1:9 will stabilize a 160 gr 6.5mm pill just fine. of course, the only way to be sure is to get some and try it out. if it doesn't, don't worry, the .264 WM has a habit of shooting out barrels in around 2,500 rounds so you'll have to replace it sooner or later anyway then you can get a new barrel/twist/groove. but really, in the mean time, there really isn't any advantage that i can see to spend the money for a new barrel if yours shoots fine now.

Bobby

 

[627PCFan]

I split the difference when I built my f-class gun in 6.5 Swede and went 1 in 8.5 since I knew I was going to run 140grainers. As far as pressure, I would expect more. You would have a faster twist and hence more resistance, a plain heavier bullet, and if your running 160 Round noses more bearing surface for resistance.

Your good to go as is IMO.

 

[NCsmitty]

The extra velocity that a 264 Mag is capable of producing over a 6.5x55 may be enough to stabilize the 156-160gr bullets offered, with the current twist.
As Bobarino mentioned, there's one way to find out.



NCsmitty

 

[USSR]

I split the difference when I built my f-class gun in 6.5 Swede and went 1 in 8.5 since I knew I was going to run 140grainers.

+1. I did the very same thing with my Obermeyer in 6.5x55.

Don