Not a hammock question per se, but this seems like a great place to get info from a lot of different folks, so I figured I'd ask.

Is anyone familiar with the military 4-piece sleeping bag system (

From what I've read, just the green "patrol bag" is good for temps down to 30* and the inner black "intermediate cold weather bag" is good down to -10*. I assume that -10 is actually both the black and green together, but I'm not sure. If so, I'm wondering what kind of temperature rating JUST the black part has without the green outer bag. Anyone know? I'm looking at buying a bunch of these inner black bags (no green part) for group campouts, but I want to make sure they'll be reasonably warm for spring/fall camping (i.e. 40-50*).

Thanks for any info you can offer!