When examining a metallic cartridge for a centerfire rifle, which of the following characteristics, if present, would unequivocally indicate that the cartridge is unsuitable for firing and must be safely disposed of?

Question: When examining a metallic cartridge for a centerfire rifle, which of the following characteristics, if present, would unequivocally indicate that the cartridge is unsuitable for firing and must be safely disposed of?

Answer options:

• A noticeable discoloration of the casing from prolonged storage.
• A slight indentation on the primer that does not penetrate the surface. ✅ A visible crack extending from the case mouth down the shoulder of the cartridge.
• A minor scuff mark on the bullet's ogive, not affecting its overall dimensions.

Correct answer: A visible crack extending from the case mouth down the shoulder of the cartridge.

Explanation: A visible crack in the cartridge case, especially extending from the mouth and down the shoulder, indicates a structural weakness that could lead to a catastrophic case failure upon firing, potentially causing severe injury to the shooter or damage to the firearm. Such a cartridge must be safely disposed of without attempting to fire it.