The Artic Warfare rifle is specially designed to endure extreme cold temperatures. It has a deicing feature that allows it to be operated as low as -40°C (-40°F). Which is really good news! Bad news is the mean temperature in Antarctica is -57°C (-70°F). Did I mention Antarctica has the record for the lowest temperature recorded over land? A chilling -89.2°C (-128.6°C)!!!! At that temperature your car's exhaust snows CO2 flakes. That's right! No fear of suffocating with your car exhaust, no sir, it's going to be snowing dry ice!!! I know there's a joke to be made there somewhere, but I digress.
Extreme cold is definitely bad for weapons, but sooner or later the party is going to enter some warm place, like a shelter or building and that's going to make things so much worse!!! An extremely cold weapon will quickly condense water on its surface. That means it will build up dew drops inside it which will freeze up again the weapon exits the building. Isn't this just wonderful? A five minute chase in and out a building is enough to render all your firearms useless. I can't buahahahahaha loud enough! Am I an evil GM or what?!?!
Here are a few things that make weapon use in extreme cold weather problematic (aside from issues with the ammo itself) :
- Lubricants become very thick and may even freeze too. Weapons may have to be used without any lubrication so as to prevent stoppage. Fortunately our players are on a government sponsored trip and will have access to United Bio Lube's "Bio Arctic", which is rated at up to -50°F. Which is good for Antarctica's summer, but come winter and well... buahahahaaha....
- Air humidity. As mentioned before bringing a cold gun into a warm room will immediately cover it with a thin film of water that will quickly freeze if the weapon is once again taken outside. This ice can block the internal components even when the weapon is completely dried on its outside. Aside form jamming, this can be damaging in gas or short throw piston weapons.
- Rapid heating. Remember the T1000 scene? Or better yet the Aliens 3 scene? Hot then cold or cold then hot can be damaging to a weapon. Rapid increases in temperature can begin fracturing the barrel. Rounds should be put down range at a slow pace before the weapon is placed in a higher full auto o cyclic rate.
- Accidentally firing the weapon. It's cold and the character has big gloves on that make it hard to feel just how much pressure is being placed on the trigger. Even with a modified trigger and more room for a gloved finger firing the weapon with precision can be a challenge. Option b is exposing the finger during the shot, but that endangers it to frostbite, and numbness can be as bad if not worse than the glove itself.
- Air density. Last, but not least, air gets denser as temperature drops. About 1% for every 4.5°F (about 2.5°C). This will affect the range and effectiveness of the weapon.
If this wasn't enough did I mention they're going against the masters of cold weather warfare? The Russians and their AK-47, good luck!
New Zealand Army - SAS cold weather training in mountain environment.
An Afghan soldier in Kamdesh, a village in the Nuristan province of Afghanistan. Winter 2006,http://news.bbc.co.uk/2/hi/in_pictures/7333540.stm