When I go places i carry two SBR's in a pelican 1720. But I also can carry 1, 2 if i really wanna fill the bag, in a VERY slim Oakley school bag. It has a "laptop" compartment, that fits the lower perfectly and protects the lower from being scratched by the upper. Has a Second compartment that can fit another lower or upper. Also pockets on each side and small compartment in the front that'll fit a few mags. More discreet than the noveske bag.
This is my backpack, Bought one a week ago at the Oakley store for 30 dollars.
http://www.ebay.com/itm/NWT-Oakley-Peak-Load-Pack-Backpack-25L-Laptop-Bag-Black-NEW-/261567622878
my brother carries his in this:
http://www.surfoutlet.com/ProductDetails.asp?ProductCode=8116138-0001&gclid=CIfYqf-chcECFZTm7Aod7GEAmg#color=27248
significantly bigger in every dimension. doesn't hold the rifle still very well in my opinion.
I also have a "tactical bag" that fits my 5.5 inch 9mm SBR broken down in. But wouldn't fit my 10.5 inch upper. I don't ever use it since I don't wanna draw attention to it.