I have one I got from Academy called 'tactical performance' that claims to be a double rifle case, but only if they are made from rubber otherwise they would beat each other to death due to no divider. I use it for my single .308 AR. It was around $35
I have a
VISM double rifle backpack bag and it's awesome. Very similar to the Savior one listed above. I think they're $58 on Amazon, and worth every penny and more. It has alot of built-in cinch strap plus zipper compartments, plus you can add MOLLE pouches and attachments. And the shoulder straps make carrying a full double rifle load out plus ammo doable. I have a fully loaded Magpul D-60 and probably 10 full 30rd mags in mine and I can tote it plus another 2 bags into the range with no issues. This bag holds alot of crap.....and never had construction issues.
I have a Drago double bag that I would like to have my money back, but I use it for AR pistols so it's good for that. Doesn't have nearly the storage or protection as the NCSTAR-made VISM bag.
I also have a
VISM range bag that I bought at the Dixie show on Saturday that is awesome. Unfortunately for me, they don't make it in Woodland camo so I can't match my rifle case :/