Bert Irslinger Jr., who owns the store with his father, says he sees nothing inappropriate about selling the type of weapon that was used to murder the people that weapon might now help financially.
"We wanted to do something for the loss of lives and injuries that happened to people in Orlando," told The Chicago Tribune.
"We don't look at this as a gun issue. We look at this as a terrorism issue," said Vic Santi, the store's marketing director.
But the mother of a victim of another mass shooting, this one in the movie theatre in Aurora, Colorado, disagrees.
Kathleen Larimer's son, John, 27, US Navy sailor from Crystal Lake, was among 12 people killed in the Century 16 theatre in 2012.
"Guns are not toys," she told the outlet. "They should be taken seriously. I'm not saying they should be illegal, but raffling off a gun is not taking its killing power seriously."
The winner of the raffle will be named July 31.
People on the store's Facebook wall were mixed in their reactions to the raffle prize.
"How dare you use the tragedy in Orlando, my town, to promote your business. I am sure the families of those affected do NOT want your money. You are a shame to society!!" wrote Sandy Weber Allen.
"Are you out of your f****** mind. You are going to raffle off the same type of gun used in our countries worse mass murder and then donate the proceeds to the Orlando victims. God will surely punish you for your hate filled ways," said Schmitt.
"You're literally raffling off a chance for this to happen again," wrote Carly Hanson.
Others, however, defended the raffle. "Really? They are donating money to support the One Orlando Fund and you are finding a problem with that? YOU are the shame to society!" wrote Keith Link.
