Polymer Ammunition Cases

[WARFAB]

I saw this ammo on the cover of a gun magazine and thought it looked interesting. If I recall correctly, this isn't the first take on polymer cased ammo. Using a polymer case raises a number of natural questions for anyone who has a decent understanding of firearms and ammunition. I figured their website might have a FAQ section that addresses the most common questions but it doesn't appear to.

http://www.truevelocityinc.com/

One of their listed features seems more than a little suspicious to me:

REDUCES WEAPONS SIGNATURE.Weapon remains cooler. Provides substantial flash reduction. Spent casing is cool to touch.

I'd be surprised if weapons remain cooler while using polymer cases, especially when they're pointing out that the spent cases are cool to the touch. Does the casing material provide a high insulation value? Ejecting a hot brass case usually has a bit of a cooling effect on a firearm.

[camper4lyfe]

Yeah, you'd think it would actually raise internal temperatures since the ejected case is removing some of the heat that would now have to be expelled through the barrel and receiver. The total heat is still the same, where it goes will be different.