To hold my XM177 and my M4 along with my HK, I bought a budget rifle case from Voodoo Tactical. The one I chose was the Voodoo Tactical 36" Padded Weapons Case - Army Digital Camo 15-7613
I read a few reviews on their products via Amazon and thought its worth a try. After all, I didn't feel like spending $140 on a Boyt bag and at $89 - I thought it was worth the risk.
The bag itself is well made. It seems durable but I haven't put it through a lot of wear and tear yet.
General Purpose: Protect the rifles while in transit from home to range. Using it at the range as a mat.
Storage: Good, plenty of zippered pockets to store magazines, pistols and ammo.
Zippers: Strong big zippers but not YKK zippers.
Straps: Weak. The straps and D rings look weak. I ended up swapping the strap from my overpriced Boyt bag for the Voodoo straps. The Voodoo bag also came with backpack straps but I doubt I'd ever carry this like a backpack. The straps are the only complaint I have with this bag.
Summary: Overall, I like this bag a lot. With shipping the bag came in just over $100 and for a bag that is made out of durable nylon, plenty of storage, good padding, decent carry handle: 4 stars. I'd buy another one if I needed one but I think the next thing in queue is a CMMG Evolution 22LR conversion kit for the XM177 and the M4.