From Yahoo:

In the wake of high-profile mass shootings, corporate America has been taking a stand against the firearms industry amid a lack of action by lawmakers on gun control. Payment processing firms are limiting transactions, Bank of America stopped providing financing to companies that make AR-style guns, and retailers like Walmart and Dick’s Sporting Goods imposed age restrictions on gun purchases.

The moves are lauded by gun-safety advocates but criticized by the gun industry that views them as a backhanded way of undermining the Second Amendment. Gun industry leaders see the backlash as a real threat to their industry and are coming to the conclusion that they need additional protections in Congress to prevent financial retaliation from banks.