It is not possible for authorities to trace the rifle used in this week’s shooting at the Holocaust Memorial Museum to the original purchaser, a law enforcement source said Friday. The source, who was not authorized to speak publicly about the investigation, said the weapon is a Winchester Model 6, .22 caliber rifle — a type of gun manufactured between 1908 and 1928 — long before records were kept on gun purchases. Authorities also were checking to see if the weapon had been used in any other crime, the source said.
