Your 590 has a 3 inch chamber. Any bird that you kill be perched in a tree or on a power wire. The 590's cylinder straight tube barrel will be a 35 yard bird barrel. I would buy premium grade number 6 shot shot 3 inch shells. The heavy payload and premium components like the best wad and hard shot might give you an edge. You might find them useful for shooting dogs and cats, city pigeons, stray chickens, and such. Boom noise will attract human predators. For your 590, buy an extra ejector, extra ejector screw, and an extra set of the parts serving as shell latch and interruptor. Just in case you lose any of this when stripping for cleaning or if the original equipment fails.