In Texas it also depends on what you are hunting with it and whether or not you own the property. If you are hunting predators or nuisance animals (feral hogs) on your own property, then there is no problem at all with either length or magazine capacity. Plus if the above is the case, you don't even need a license. But if you are talking about game animals then the TPWD annual states: "White-tailed deer, mule deer, desert bighorn sheep, and pronghorn antelope may not be hunted with rimfire ammunition of any caliber." There is no restriction on magazine capacity or rifle length other than it must be a legally owned firearm and not fully automatic. I hunt hogs with my carbine and my Colt M-4 with 30rd mags in them. But I usually hunt deer and other game animals with a bolt gun. I have a friend who has often hunted deer with his carbines. So it should be fine.
