We are confident that the courts will vindicate our view that Florida’s ban is a blatant violation of the Second Amendment," the NRA said in a statement.
"This blanket ban violates the fundamental rights of thousands of responsible, law-abiding Florida citizens and is thus invalid under the Second and Fourteenth Amendments," the lawsuit reads.
"This is a first step, and if we really want to do something to combat gun violence, like what we saw in Parkland, we must require universal background checks on the purchase of a gun and get these assault rifles off our streets," said Sen. Bill Nelson (D-FL).
"Waiting periods, gun violence restraining orders, and 21 to buy a gun are what the people want," said Rep. Ted Deutch (D-FL), "but the gun lobby, the legislature and the governor must know that this is just the beginning and not the end of the response."
Since the Florida shooting, the idea of raising the purchase age to 21 has drawn interest from President Donald Trump, though a day after he expressed his public support, NRA officials met with him at the White House, and urged him to back away from the idea.
Some in Congress have expressed interest in a similar plan, but GOP leaders seem unlikely to allow a vote on the idea.
Next week, the U.S. House will vote on a plan that would funnel $50 million in grant money to states, to help schools better prepare for how they would deal with people who might resort to violence.