This is the police sergeant who fired a crazed gunman square in the chest from 312 feet away while holding the reins of two horses in one hand. Adam Johnson, of Austin Police Department in Texas, was on mounted patrol at 2.33am when Larry McQuilliams tore past him firing more than 100 rounds at buildings using AK-47 and .22-caliber rifles. The pre-dawn rampage the day after Thanksgiving came to an abrupt halt when Johnson responded with one pistol shot that has made him a hero in the eyes of gun-proud Texans. Scroll down for video . Incredible shot: Sgt Adam Johnson was holding two horses with one hand when he fired at crazed gunman Larry McQuilliams, 49, whom he saw tearing through Austin, Texas, firing with two rifles 312 feet away . 'I would say what this officer did was phenomenal, especially if he didn't brace his arm against anything,' Army Major John Plaster, a long-range shooting expert, told Fox News. Plaster added: 'At minimum it was an extraordinary shot.' McQuilliams, 49, was pronounced dead at the scene. A post mortem examination will confirm whether it was Johnson's Smith & Wesson M&P .40 pistol which dealt the fatal shot. Rampage: McQuilliams was armed with numerous weapons and hundreds of rounds of ammunition on his raid . Attack: He had a map of 34 downtown Austin buildings which he appeared to be targeting with two rifles . An initial investigation found McQuilliams was following a meticulously mapped route of the city's downtown buildings - including the Mexican consulate, the federal court house and a bank - armed with numerous firearms and hundreds of rounds of ammunition. Johnson was leading a 12-member patrol unit shortly before his shift was due to end. 'For a guy to keep his composure and holding two horses with one hand and taking a one-hand shot with the other hand, it says a lot about the training and professionalism of our police department,' Austin Police Chief Art Acevedo said.
Sgt Adam Johnson was on mounted patrol at 2.33am in Austin, Texas .
Crazed gunman Larry McQuilliams, 49, tore past firing with AK47 .
Johnson holding two horses as he fired shot that took McQuilliams down .
This is the police sergeant who fired a crazed gunman square in the chest from 312 feet away while holding the reins of two horses in one hand. Adam Johnson, of Austin Police Department in Texas, was on mounted patrol at 2.33am when Larry McQuilliams tore past him firing more than 100 rounds at buildings using AK-47 and .22-caliber rifles. The pre-dawn rampage the day after Thanksgiving came to an abrupt halt when Johnson responded with one pistol shot that has made him a hero in the eyes of gun-proud Texans. Scroll down for video . Incredible shot: Sgt Adam Johnson was holding two horses with one hand when he fired at crazed gunman Larry McQuilliams, 49, whom he saw tearing through Austin, Texas, firing with two rifles 312 feet away . 'I would say what this officer did was phenomenal, especially if he didn't brace his arm against anything,' Army Major John Plaster, a long-range shooting expert, told Fox News. Plaster added: 'At minimum it was an extraordinary shot.' McQuilliams, 49, was pronounced dead at the scene. A post mortem examination will confirm whether it was Johnson's Smith & Wesson M&P .40 pistol which dealt the fatal shot. Rampage: McQuilliams was armed with numerous weapons and hundreds of rounds of ammunition on his raid . Attack: He had a map of 34 downtown Austin buildings which he appeared to be targeting with two rifles . An initial investigation found McQuilliams was following a meticulously mapped route of the city's downtown buildings - including the Mexican consulate, the federal court house and a bank - armed with numerous firearms and hundreds of rounds of ammunition. Johnson was leading a 12-member patrol unit shortly before his shift was due to end. 'For a guy to keep his composure and holding two horses with one hand and taking a one-hand shot with the other hand, it says a lot about the training and professionalism of our police department,' Austin Police Chief Art Acevedo said.
in Texas, was on mounted patrol at 2.33am when Larry McQuilliams tore past him firing more than Scroll down for video . Incredible shot: Sgt Adam Johnson was holding two horses with one hand when he fired at crazed gunman Larry McQuilliams, 49,