Gunsmithing .308 tensioned barrel? Possible or a waste of my time?

[BenY 2013]

So I have been doing a little bit of research about tensioned barrels lately. As I understand it a very skinny barrel is put under pressure from both ends reducing the whip of the barrel. I know that is a pretty basic explanation, but I still barely understand it myself. So I have a few questions about doing this.

How does the very thin barrel, then the air space between that and the outer shroud affect the heating up of the barrel?

I am considering using carbon fiber as the shroud or should I go with aluminum?

Will this type of this stand up to a .308?

What are some of the steps I should take in machining this? Does the carbon fiber or aluminum shroud need to be threaded to the barrel, or will just a very tight slip fit work? Thanks guys!

Ben

 

[Stonewall2]

Try that question on the Benchrest.com forum.
There are several shooters there that have experimented with this concept.

Glenn

 

[buffybuster]

Other than pure experimenting, what are trying to achieve that is not already available with a standard cantilevered barrel?

 

[BenY 2013]

Other than pure experimenting, what are trying to achieve that is not already available with a standard cantilevered barrel?

Mostly reduced weight. I am also very curious to try!

Ben

 

[bohem]

I have seen a bunch of rifles with light contours that shoot dimes even on long strings. A friend of mine had a 6 Rem AI that was pushing a "mild" 105 Amax at 3175 and it was a beanfield rifle, #3 contour and we could just pound things with it at distance. The limiting factor was barrel heat induced mirage, one time just for kicks we put a box fan at the shooter and put 20 rounds through it. The box fan pushed away the mirage and at 500yd the gun kept a 2" group. 6 Rem AI barrels don't last very long and neither did this one, but it was an "awakening" moment where I started to like heavy contours less and less.

The light palma has been shown to pound in 308 for thousands of rounds, what's the point of all the work if you can put a top grade barrel on a rifle and not have to deal with the pre-tension issue?


Now, if you DO decide to do it, there's a Precision Shooting article about this from about 2009 IIRC, the guy takes a light contour barrel and shows that he gets some mild accuracy improvement but to do so he had to spend a painstaking several days at the range tuning the torque for the load. It seemed like an awful lot of work to take a rifle that was already shooting 1/3 MOA to 1/4MOA, for field rifles that's more than adequate to begin with. In short range BR that's not an acceptably competitive rifle to start with even at 1/4 MOA, so you'd better start with something that shoots in the teens.

 

[BenY 2013]

I just want the looks of a varmint weight barrel with the weight of a sporter, which also has the accuracy I am wanting sub-moa. I am not wanting to sink alot of money into this, just wondering what some opinions of the Hide members were. I will see if I can find the article you mentioned. Thanks

Ben

 

[AKA-Spook]

p.m.'ed ya Ben

 

[MarinePMI]

IIRC, there was an Israeli company that offered/made CF tensioned barrels for one of the high end manufacturers. I can't remember the name right now (having a CRS moment right now; "can't remember shit"), but I remember them well. At the time they were the en vogue thing...nothing new, just new materials...

Heck, even Dan Wesson wheel guns used to have tensioned barrels; and they worked well.

 

[DAVETOOLEY]

Food for thought. Instead of putting the barrel in tension where the preset load changes as the barrel heats up why not put the barrel in compression?
And yes I've done that.

Dave