PHILADELPHIA — Hand-painted signs in Amish country often advertise fresh eggs, shoofly pies or handmade quilts, but the Bureau of Alcohol, Tobacco, Firearms and Explosives is trying to determine whether one Lancaster County farmer’s sizable gun collection was also his side hustle. An ATF spokesman said agents seized evidence during an “enforcement operation” on Jan. 12 at the Cattail Foundry in Leacock Township, Lancaster County, but declined to comment further. Two sources familiar with the investigation said approximately 600 firearms were seized during the operation. On Wednesday morning, f...