A serpentine dispenser and cartridge system provides simplified stocking and restocking, as well as jam-free dispenser feeding. A cartridge priming flap allows a cartridge be inverted and inserted into a dispenser while products in the cartridge are prevented from falling out. Cartridge opening is completed by holding an priming flap while pushing the cartridge into the dispenser. In other embodiments, a dispenser wedge applies pressure on rolling products, forcing a retaining flap open, as the cartridge is pushed into the dispenser. The wedge can also constrain rolling products to exit the cartridge in an order that prevents jamming.