.22 LR (Long Rifle) is a popular rimfire cartridge known for its low recoil, affordability, and versatility in target shooting, training, and small game hunting. While not a manufacturer, many firearms companies produce .22 LR-specific parts, including barrels, upper receivers, magazines, bolt carrier groups, and complete rifles or conversion kits. These components are widely used in AR-15 platforms, handguns, and dedicated .22 LR firearms, making them ideal for beginners and experienced shooters alike. If you need info on a specific manufacturer of .22 LR parts, let me know!