The Remington 597 hammer is fully machined (no casting or stampings). The hammer notch is then individually surface ground to assure an exact angle of engagement. It will provide a 50% (approximately) lighter trigger pull. It is designed to be used in an unaltered factory trigger guard. Made of A2 tool steel, fits 22 Long Rifle, 22 Magnum and 17 HMR. Gunsmith installation required.