Is the new Mossberg 590RM the best pump action shotgun? 1ShotTV takes a look, highlighting its upgraded features compared to the classic 590. These upgrades include a larger magazine capacity, an improved buttstock design, an AK-style magazine release, a heat shield, and M-LOK slots. The test included various types of ammunition, all of which cycled flawlessly. The 590 RM also demonstrated impressive accuracy, hitting a steel plate at 100 yards.