Horrifying History on Instagram: "On Wednesday, April 8, 2009, 44-year-old Marie Moore and her 20-year-old son, Mitchell Moore, arrived at the Shoot Straight gun range in Casselberry, Florida. Surveillance footage showed them renting a 9mm pistol and purchasing ammunition before entering the range. They took turns shooting at targets for approximately 20 minutes. The footage then captured a horrifying sequence. Marie Moore, standing behind her son as he aimed at a target, suddenly raised her ren