Too cold for SS barrels?

[crazymoose]

I periodically read claims that stainless barrels are a poor choice for very cold weather. I could only dig up one thread about this from almost a year ago, and the info was somewhat sketchy.

Does anyone know what the potential problems with this could be? Does stainless steel become brittle more quickly as the temperature drops than carbon steel? Is it a chamber lubricity and case extraction issue?

I have a Noveske SS barrel that I'd like to put through its paces outdoors this winter. Temps probably won't get any colder than -10 Faranheit. Should I keep the stainless barrels in the safe and only shoot the 4150-barreled guns in this weather, or is the concern for stainless in cold weather not justified?

[Abraxas]

I have fired my stainless barreled weapons in subzero temps with relatively no issues. At least not from the barrel anyway.

[KyAKGuy]

Does stainless steel become brittle more quickly as the temperature drops than carbon steel? Is it a chamber lubricity and case extraction issue?
Should I keep the stainless barrels in the safe and only shoot the 4150-barreled guns in this weather, or is the concern for stainless in cold weather not justified?

You'd have to cool it WAY down to get it brittle enough th be a problem.
Drop it in a tank of liquid Nitrogen or Helium, then drop it.
It would probably shatter like a glass rod. It won't get any more brittle at cold earthly temperatures,
so i wouldn't worry.
Unless you are doing something like recovering Chinese spy
satellite film canisters in Antarctica in July...
You worry is unfounded.

KyAKGuy

[theJanitor]

^i use liquid nitrogen in my work all the time, i've never gotten metal/stainless cold enough to shatter.

[sniperfrog]

On Boots Obermeyers web page he talks about this. In subzero temps stainless will get brittle and with light contour barrels there is the possibility that it will rupture. Boots is talking from experiance. I would say it would have to be pretty freakin cold because I've shot 300 Win Mag in Alaska in -25 F without any problems.

[Stan_TheGunNut]

Regular carbon steel barrels are more likely to suffer from the cold more than stainless steels. I say this because at work we sometimes use freeze seals to act as valves in water pipes. Liquid nitrogen is kept as a backup, but typically we use vortex freeze seals which only requires pressurized air. With the vortex system, the steel only gets to about 20 below zero, so we don't have to worry about the carbon steel fracturing. With stainless, you can go much colder before you have to worry about the fracture temperature. I don't recall the exact numbers though.

One can do some research on brittle fracture of steel. Look at what happened to some of the liberty ships of WWII. They literally broke in half due to the cold water of the North Atlantic.

[STJ]

Here is just one quote from AZOM.COM.

Grade 416 has the highest machinability of any stainless steel, at about 85% of that of a free-machining carbon steel. As for most other free-machining stainless steels the improvement in machinability is achieved by addition of sulphur which forms manganese sulphide inclusions; this sulphur addition also lowers the corrosion resistance, weldability and formability to below that of its non-free machining equivalent Grade 410.

Grade 416 is sometimes used in the unhardened or hardened and highly tempered condition because of its low cost and ready machinability.

Martensitic stainless steels are optimised for high hardness, and other properties are to some degree compromised. Fabrication must be by methods that allow for poor weldability and usually also allow for a final harden and temper heat treatment. Corrosion resistance is lower than the common austenitic grades, and their useful operating temperature range is limited by their loss of ductility at sub-zero temperatures and loss of strength by over-tempering at elevated temperatures

[bullseye]

allow me to add one pearl of wisdom to this dis-cussion-----if it's -10 to -25 outside... STAY HOME!!!!! by the fireplace.

[LOKNLOD]

One can do some research on brittle fracture of steel. Look at what happened to some of the liberty ships of WWII. They literally broke in half due to the cold water of the North Atlantic.

True but IIRC the major factor in the liberty ships breaking completely in half was based on their welded construction instead of riveted. This allowed cracks to propogate completely instead of being stopped when reaching the edge of individual steel plates.

But on the same issue, and as mentioned in the quote about adding sulphur, one of the theories I remember about the sinking of the Titanic was that the steel used had too high of a sulphur content, and the ductile-brittle transition temperature was higher than would be expected. That would again contribute to the iceberg ripping in and the ship breaking in half.