I own a 50.5 inch Rifle and the blackhawk drag bag that I can find for cheap is 51 inches and I dont want to take a chance on it not fitting. I also dont like how a ton of others have extras that I dont need.
So when I am looking to get a dragbag that I can carry my rifle in while I walk/hike to my final hunting area.
right now I have a Mystry Ranch 3 day assault pack that I use on my daily/3 day long hunting trips and I have a NICE Frame Crewcab that I use on everything beyond that or when I need extra stuff or room to carry you know what
In all I am looking to get a minimalist drag bag/shooting mat combo, I am open to getting something that doesnt have the mat but not willing to get a mat that isnt a drag bag...if that makes sense.
I was looking for the same thing as my rifle is 51 inches. Ordered the voodoo tactical ultimate drag. Its not a mat but is a pretty sweet bag. Fairly compact for what it is and comes with backpack straps.
Found a good deal with free shipping at patriotsurplus online. I could not find a bag mat combo for a rifle as long as ours. Its 53" and they claim it handles a 51" rifle. They didn't lie, mine fits fine.
Try Midwayusa's tactical drag bag, they come in two lengths, I believe 50' and 56' And are of great quality. I just ordered one for I think 70 bucks. They should fit the bill, given what you described you were looking for.