I bought a shelter half this weekend and rolled it up, here is what I ended up with. It is a little fat because I have a doubled up piece of batting in the center but I can take more pictures without the insert.
https://drive.google.com/file/d/0BzN6V0cECEpXdUxjTE5yZVNKeEk/view?usp=sharing
It measures out to 46 inches the way I have it rolled, the USMC manual states that it should be the length of one tent post. The tent post happens to be 43.5 inches.
What do you all think?