Measurements - Thread Length: 6mm, Cone Length: 6mm, Total Length: 17mm, Shoulder width: 6.35mm. TRESO nipples are made from Ampco, a tough alloy with a tensile strength of 118,000 psi, which is tougher than most steels used in muzzleloading barrels. This material provides more resistance to blows from the hammer, and the high thermal conductivity of Ampco alloy affects a faster heat dissipation. This dissipation reduces erosion of the small base hole and assures a longer lasting nipple. All nipples have a small base hole (.028”) to greatly reduce the amount of escaping powder gases. Many muzzle loading experts feel an added benefit of the small base hole is the hot gases from the percussion cap are more concentrated and uniformly directed against the powder chamber.