Cartridge Brass Cartridge Case Cups

B129-12: Standard Specification for Cartridge Brass Cartridge Case Cups

In the demanding fields of defense and ammunition manufacturing, the integrity and reliability of every component are paramount. For professionals involved in the production of cartridge cases, understanding and adhering to the ASTM B129-12 Standard Specification for Cartridge Brass Cartridge Case Cups is essential. This authoritative document provides the foundational requirements for the critical raw material used in the fabrication of high-performance ammunition, ensuring consistency and quality from the outset of the manufacturing process.

What is B129-12?

ASTM B129-12 is a comprehensive industry-leading standard that defines the material, manufacturing, and quality control requirements for annealed cartridge brass cups. Originating from ASTM International's commitment to material science and engineering excellence, its primary purpose is to establish a uniform basis for procuring and producing these vital components for subsequent fabrication into cartridge cases.

Scope & Purpose

This standard governs the production and acceptance of annealed cartridge brass cups made from Copper Alloy UNS No. C26000. It specifically details requirements for two types: Type I for small arms and Type II for artillery cartridge cases. The specification covers chemical composition, temper, grain size, and essential dimensional tolerances, ensuring the cups are suitable for deep drawing and other forming operations inherent in cartridge case manufacturing. It does not cover the final cartridge case dimensions or performance characteristics.

Who Must Comply?

• • Primary audience: Materials Engineers, Metallurgists, Quality Control Inspectors, Manufacturing Engineers, and Production Supervisors involved in ammunition and defense component manufacturing.
• • Industries affected: Defense, Ammunition Manufacturing, Metals Manufacturing, and Ordnance production.
• • Compliance nature: While primarily a specification for procurement and quality assurance, adherence is often contractually mandated, especially for government agencies, making it effectively required for relevant supply chains.
• • Enforcement: Compliance is typically verified through internal quality control processes, supplier audits, and by end-users or government procurement agencies during acceptance testing.

Key Requirements Overview

The standard requires that cartridge brass cups be manufactured from a specific wrought alloy (UNS No. C26000) in an annealed temper. Professionals must ensure that the material meets stringent chemical composition limits for copper, lead, iron, bismuth, and zinc. Key provisions include specifying acceptable grain size ranges for the sidewall, critical for the material's formability, and defining requirements for uniformity and freedom from surface defects that could compromise performance. Furthermore, the standard outlines detailed sampling and testing procedures for verification of these properties.

Related Standards & References

ASTM B129-12 is a foundational document that works in conjunction with other ASTM standards. ASTM B601, which classifies temper designations for copper and copper alloys, is referenced for defining the annealed temper (OS). ASTM B846 provides essential terminology for copper and copper alloys. Additionally, standards like ASTM E112 for determining average grain size and ASTM E255 for sampling copper alloys are critical for conducting the required tests and ensuring conformance.