The M90A is our 454 Casull rifle. It is a very nice bridge between smaller caliber rifles like a 44 Mag and lager calibers like the 500 S&W. With the 18″ Barrel the rifle can hold 7 rounds in the mag tube plus one in the chamber. One round is enough to stop almost anything and even if it turns out not to be you still have over half a dozen more rounds to put into the target. Easy to control and with a widely available ammo it is easy to feed as well. It is a great rifle to have and very useful for almost any situation. That being said if you are wanting to stop a charging buffalo it still might be a better choice to go with the M89!