The FBI found more than 150 homemade bombs during a raid on a Virginia farm when they arrested a man on a firearms charge, federal prosecutors allege. The big picture: Preliminarily assessments of the haul seized from Brad Kenneth Spafford’s Isle of Wight County farm indicate it’s “the largest seizure by number of finished explosive devices in FBI history,” per a court filing from federal prosecutors. His defense lawyers say there’s no evidence…