Vista Outdoor Inc., an ammunition and gun manufacturer, spent more than $1 billion in recent years to scoop up consumers brands like Camelbak water bottles and Giro bike helmets to diversify its business.

But that strategy has backfired after the Parkland, Fla., school shooting prompted some retailers to say this week that they will stop ordering the company’s outdoors and consumer products because Vista also manufactures AR-15-style semiautomatic rifles.

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