Was An Assault Rifle Used in Both U.C. Shootings?

Officers have reported finding 7.62 caliber rifle casings at the scene of both recent U.C. shootings. The AK-47 and similar assault rifles use this ammo.  In the latter shooting, involving the boys, 10 to 11 7.62 casings were found at the scene per radio traffic.  At the scene of the first shooting on November 20th, where two men were shot in their parked car, one 7.62X39 casing was found.  The officer speculated that there may have been a mix of rifles and handguns used, but only one casing was reported located.  Detectives may be able to tell from the casings if the same model weapon was used at both crime scenes.