a bag opening apparatus comprises a pair of pivotable pins mounted on a movable carriage . the carriage is mounted on the rod of the first piston and cylinder assembly so that is may move in and out of proximity with a stack of mesh bags to be opened and filled . the mesh bags are supported on one face only so that the opposed face may be opened by inserting the pins into the bag and moving the pins outward to engage the mesh faces . only the face which is not suspended will be opened as the pins are drawn away on the movable carriage . a second piston and cylinder assembly includes a stop pumper which is located to control the extent that the carriage is retracted and to thereby control the extent of the bag opening .