Those Featheweight barrels are kind of thin. A little more meat and the accuracy might be more consistant. Weight can be saved in other areas besides the barrel.

On the other hand if 1.5 MOA is ok then such a thin barrel will hold the pressure. I have got them shooting one MOA with a lot of work. Once in a while they even do better. An aftermarket barrel might be better than my factory barrels and maybe not.

I would rather take the weight out of the stock, action and scope before the barrel.

It depends on the steel, the heat treat, the finish, the shape, etc.



For general formulas and the yield point of the steel:

1) Thin walled tube hoop stress, S = Pressure [inside diameter] / [twice the thickness]

2) The above is for bannana peel failures, for breaking off the lizard's tail, the stress is half that. That's why you can make band like cuts into a barrel, and you seldom see barrels fail anyway but lengthwise.

3) Thick walled stess is from Lame's formula,

S=P(r2 squared +r1 squared)/(r2 squared - r1 squared)



Where S is the stress in psi of tension



P is the chamber pressure in psi



r1 is radius of the chamber or bore in inches



r2 is radius of the barrel [center to outside] in inches"







================

If the flutes are lengthwise, measure from the bottom of the flute for hoop stress.

Clark,



I don't know what stainless is typically used, but you could give this guy some idea of what the yield stress probably is, so the calcs mean something.

The barrels on M70 Featherweights and Savage 99F's in .358 are .56" at the muzzle. This diameter has proven itself, strength wise, over time.

I would not flute such a thin barrel due to stress raisers as mentioned above.

Most barrel makers will not make a barrel with less than .125" wall thickness at the muzzle... on a .358 that would mean no less than .608" at the muzzle... get one contoured at .610" - .625" but pay more attention to the barrel shank. That's where most mfg's leave a lot of metal (and weight). Douglas has very sane contour's... on most contours their visible shank length is no more tha 1.250", whereas other makers go as much as 3". Another way to do this is have someone (PacNor is good at this) duplicate the Winchester Featherweight pattern... it has a little .300" shank with radius that tapers to .560" at 22"... they could program their CNC to go to .620" at the muzzle... that's the route I'd go.

Brad

The stainless in a Ruger 454 cylinder is good to 260 ksi [and is expensive and hard to machine], but most modern SS barrels should be good to 100 ksi.

Here is a google search:
http://www.google.com/search?hl=en&ie=UTF-8&q=yield+strength+of+stainless+steel&spell=1