- 01: Introduction
- 02: History
- 03: Propellants, Firearms, and Ammunition Development
- 04: Modern Firearms Manufacture
- 05: Small Arms Ammunition
- 06: Evidence Handling Procedures
- 07: Equipment and Instrumentation
- 08: Examination of Firearms
- 09: Cartridge and Shotshell Examination
- 10: Characterization and Evaluation of Fired Projectiles
- 11: Bullet Comparison and Identification
- 12: Gunshot Residue and Distance Determination
- 13: Toolmark Identification
- 14: Communicating Results
- Resources
Bullet Seating
Home > Small Arms Ammunition > Assembly > Bullet Seating
Bullet-seating die
Rimfire bullets have the same diameter as the outside of the cartridge case. For the bullet to hold in the case, its base section is smaller to match the inside case diameter. The most common rimfire bullets are found in .22 Short, .22 Long, and .22 Long Rifle ammunition. The common term for this style is heeled bullet.
In the bullet-seating operation, the cases are held on either a continuous conveyor mechanism or in plates holding hundreds of cases. If the conveyor system is used, an alignment die falls lightly on each cartridge mouth and a bullet is fed into the die. Shaped to match the bullet tip, a seating punch presses the bullet into the case, resulting in a friction fit.
If the plate-loading system is used, cases are held in one plate and bullets in another. The upper plate serves the same purpose as the alignment die. The two plates are aligned and placed in a seating press. The ram of the press is fitted with a seating pin for each case, and all bullets are seated in one stroke.
