I picked up a Fulton Armory M1 Garand Tanker at a gun show in the 1990's at the bargain price of $450. It's in 7.62x51 caliber, which is a much better caliber for a shorter barrel length. Indeed, its 18" barrel is still 2" longer than my Springlield Armory M1A Socom. I added an original blade style flash suppressor on my Tanker and ended up with a pretty cool carbine.
Shuff's Parkerizing has been marketing a modified M1 Garand he (Tim) calls the Mini-G with a 16" barrel ! I got to thinking how the 7 round magazine on an empty chamber of 30-06 would be pretty good bear repellant, but upon learning that he also does the 35 Whelen barrel conversion, I really got interested. But 16" is too short, regardless of what he's telling me (I called and spoke with him), even with faster burning powders. A 37" rifle is super nice for carry, but I'll sacrifice another few inches of length for that velocity as long as I stay under 40" of total length.
A group of friends operated a black bear bait station for over 20 years near the confluence of the Yentna and Susitna Rivers in Alaska. During those years it was illegal to take brown bears over bait, but you could be sure they'd show up, and they'd keep you in the trees well past dinnertime back at camp. One of these engineers, a bow hunter, got a Remington 7600 pump action rifle in 30-06, bought cheap 10 round magazines for it, chopped the barrel to 16", and installed a Remington 870 shotgun pistol style grip on it for a backup gun over the standard 44 magnum revolver. Cool assault rifle for bears!