This specification establishes the requirements for manufacture and acceptance of the Projectile, 20 Millimeter (mm), Target Practice, PGU-27/B, referred to herein as the "projectile." Beneficial comments (recommendations, additions, deletions) and any pertinent data which may be of use in improving this document should be addressed to: Commanding Officer, Naval Air Engineering Center, Systems Engineering and Standardization Department (SESD), Code 93, Lakehurst, NJ 08733-5100, by using the self-addressed Standardization Document Improvement Proposal (DD Form 1426) appearing at the end of this document, or by letter.