The retailer also said that it would no longer sell high-capacity magazines and that it would not sell any gun to anyone under 21 years of age, regardless of local laws.

The announcement, made two weeks after the school shooting in Parkland, Fla., that killed 17 students and staff members, is one of the strongest stances taken by corporate America in the national gun debate. It also carries symbolic weight, coming from a prominent national gunseller…

“When we saw what happened in Parkland, we were so disturbed and upset,” Mr. Stack said in an interview Tuesday evening. “We love these kids and their rallying cry, ‘enough is enough.’ It got to us.”