Blame the weapon system or nation funding it, not the ammo...

Yes 5,56 worked damn bad in cold climates, for USAnian troops with weapons produced by the lowest bidder.

Swedish soldiers serving our King have had absolute nil such issues.

What Seamus said is right, USA used plastics for mags.

I must honestly say I was way impressed with the Swedish equipment we had. Not many forces in the world can be on 100% combat effectiveness in -47 degrees Celsius.

Such small solutions as having gloves with mittens on top, mittens having the ability to be folded back half way so we had the (gloved) fingers free to shoot, meant we could have warm fingers holding the trigger. I noticed LOADS of such small practical details that is worth life and death in a real situation :)