7mm-08 barrel choice (proof vs bartlein)

[PHX1212]

I'm building a "light" hunting rifle/occasional range gun. Main focus is weight reduction. I want a Proof, but the twist rates available limit me to a 24" 9 twist sendero contour at 49oz. Ideally I wanted a 22" 9 twist light sendero at 44oz, but they only offer a 8.4 twist. I believe that will be too fast for my application since I plan to use 140gr bergers or Sierras. I also wanted the shorter barrel for maneuverability.

My other option is a Bartlein in a #3 contour with a 9 twist. Advertised weight is 56oz at a 26" length. I wonder what the weight would be if I cut it back to 22", and had it spiral fluted. I would assume the 4" of barrel is a decent amount of weight, and the flutes would contribute a few oz loss as well.

The prices will be about the same when all work is done to the Bartlein, so cost is negligible. Any advice or experience will be greatly appreciated.

 

[elkaholic]

I'm building a "light" hunting rifle/occasional range gun. Main focus is weight reduction. I want a Proof, but the twist rates available limit me to a 24" 9 twist sendero contour at 49oz. Ideally I wanted a 22" 9 twist light sendero at 44oz, but they only offer a 8.4 twist. I believe that will be too fast for my application since I plan to use 140gr bergers or Sierras. I also wanted the shorter barrel for maneuverability.

My other option is a Bartlein in a #3 contour with a 9 twist. Advertised weight is 56oz at a 26" length. I wonder what the weight would be if I cut it back to 22", and had it spiral fluted. I would assume the 4" of barrel is a decent amount of weight, and the flutes would contribute a few oz loss as well.

The prices will be about the same when all work is done to the Bartlein, so cost is negligible. Any advice or experience will be greatly appreciated.

I did the same thing with a Brux on my 270SS. #3 fluted at 21". The rifle package, scope and all, with manners EH4 and TI Razor action weighs exactly 7 lbs

 

[PHX1212]

Elkaholic did you happen to get a weight on the barrel after the machining was done? Sounds like a great setup.

 

[elkaholic]

Elkaholic did you happen to get a weight on the barrel after the machining was done? Sounds like a great setup.

I didn't, sorry.

 

[elkaholic]

I think we figured it was as light as the proof though. It shoots .3 by the way

 

[Gregg C]

Lilja has great info about weight-fluting etc. on his website.

 

[PHX1212]

Elkaholic thanks for all the info.

Gregg I'll look at their website. Thanks!

 

[PHX1212]

Side comment...

Do you think I'm over emphasizing the twist rate? Do you think the 8.4 vs 9 twist will be noticable with 140-150 gr bullets? I noticed most manufacturers of popular brand names rarely offer barrel options below a 9.

 

[elkaholic]

Side comment...

Do you think I'm over emphasizing the twist rate? Do you think the 8.4 vs 9 twist will be noticable with 140-150 gr bullets? I noticed most manufacturers of popular brand names rarely offer barrel options below a 9.

The 8.4 is not necessary for the bullets you want to shoot although it wouldn't hurt you much either. Probably a slight velocity loss.

 

[Bimbo19]

I think we figured it was as light as the proof though. It shoots .3 by the way

+1

 

[cohunt]

Extra twist can sometimes help bullet expansion as long as it's not too dramatic--- I know a guy that did some terminal ballistic gel testing using identical ammo, barrel length, but different twist rates and an deecrease in length/twist of only 1", (ex: going from a 1:11 to a 1:10, so faster twist) actually made the bullets expand faster and to a larger diameter---especially when using barnes monolithic bullets. He said accuracy was comparable, and velocity difference was negligible

 

[PHX1212]

Cohunt that is very interesting. When using the Berger bullet twist rate calculator it shows their 140gr VLD will be stable in a 1-8.4 twist, but when I called they did not recommend that twist, and actually recommend a 1-10 which I found surprising.

 

[Kimber7man]

Are you planning on using a suppressor?
If not, a Bartlein 2b contour would be perfect for lighter weight hunting rifle. I have a 7mm08 with 22.5" Brux 3 contour which is pretty similar to Bartlein 2b. Oregonmuley was kind enough to sell it to me, he's built plenty of 7mm08's and would be a good source of info.

 

[codyadams]

The extra twist shouldn't hurt anything, if you want the carbon barrel go for it, but the fluted steel barrel would likely be lighter. According to lilja's calculator, you wpuld loose about 8 oz or so from strait fluting, probably slightly more from spiral fluting, so you would be at 48 oz or so, then have your smith cut the shank back to where only 1" of shank is in front of the action, and finish at 22", and you will be significantly lighter with the steel barrel.

Where you save weight with carbon barrels the most is of you go heavy contour. A steel barrel with a .900" muzzle is significantly heavier than a same contour carbon barrel, obviously. But you will always be able to go lighter with a slim contour steel barrel.

Another option for carbon barrels , if that's what you really want, is look at carbon six or hells canyon armory, both can get the twist/contour you want.