LOS ANGELES — A former gang member who founded an anti-violence group called No Guns has pleaded no contest to federal weapons charges. Hector "Big Weasel" Marroquin, 51, and co-defendant Sylvia Arrellano, 25, entered pleas Thursday for three counts of manufacture, distribution and transport for sale of an unlawful assault weapon. Arrellano also pleaded no contest to machine gun conversion and possessing a silencer and acknowledged that the crime was committed for the benefit of a criminal street gang. She was given until Tuesday to surrender for sentencing and would likely be sentenced to four years in prison, prosecutors said....