To be honest Mackay I am more interested in how the old 60 series held up to the cold.
It ran like a top, just never put out enough heat.
The door handles and locks were stiff to operate, and definitely could use a shot of graphite lubricant in the mechanisms.
Of course the same could be said for the firearms. A low viscosity oil would be highly recommended for temps this low.
Once I wiped off the regular teflon based lube, and was running the rifles almost dry, they ran perfectly.
I noted that the rifle powders and handgun powders are/were affected differently in the extreme cold.
Plus the extreme cold was hell on batteries. If I was planning on carrying guns in a martial capacity in sub zero temps, I would either have extra batteries along, and close at hand, or choose a non battery operated optic like an ACOG.