Lewis has done an excellent job of describing the Grey Hawk. With its synthetic stock and stainless hardware , it was Thompson Centers way of appealing to those looking for a gun that was rugged. Unfortunately some people think that because the barrel was stainless that it didn't require the care that a blued gun does. Also being a 1-48 twist does limit your bullet selection to this projectiles used for shorter range. If you hunt in wooded areas with limited range this is not a problem.
My first 2 deer were taken with a inexpensive 50 caliber Muzzleloader with a 1-48 twist using round balls and 70 grains of black powder. Both shots were under 50 yards. I often practiced shooting out to 125 yards with this gun but when it came to hunting i was looking for the under 50 yard shots.