【国外标准】 Standard Specification for Copper Alloy Bullet Jacket Cups

15.1 For the purpose of determining compliance with the specified limits for requirements of the properties listed in the following table and for dimensional tolerances, an observed value or a calculated value shall be rounded as indicated in accordance with the rounding method of Practice E29.Property Rounded Unit for Observed or Calculated Value   Chemical Composition Nearest unit in the last right-hand significant digit used in expressing the limiting value   Grain size Nearest multiple of 0.005 mmAbstractThis specification covers bullet jacket preform cups made from UNS C22000 wrought copper alloy used for processing Types I-IV and Classes I-II bullet jackets. This standard contains information on chemical composition, grain size and testing requirements for the preform cups.1.1 This specification establishes the requirements for bullet jacket preform cups produced of Copper Alloy UNS No. C22000 for processing into bullet jackets of the following types and classes:1.1.1 Type I—Caliber 0.30.1.1.2 Type II—Caliber 0.45.1.1.3 Type III—Caliber 0.50.1.1.4 Type IV—As specified in the contract or order.1.1.5 Class I—Not annealed.1.1.6 Class II—Annealed.1.2 Units—The values stated in inch-pound units are to be regarded as standard, except for grain size, which is given in SI units. The values given in parentheses are mathematical conversions to SI units that are provided for information only and are not considered standard.1.3 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.