Gunshot
The proper location of gunshot penetration is important in the destruction of the brain and minimizing suffering. The optimal site for penetration of the skull is one-half inch above the intersection of a diagonal line from the base of the ear to the inside corner of the opposite eye. The firearm should be aimed directly down the neck, perpendicular to the front of the skull, and held at least 2-6 inches away from the point of impact. When performed skillfully, gunshot induces instantaneous unconsciousness, is inexpensive, and does not require close contact with the horse.
A .22-caliber long rifle is recommended, but a 9mm or .38-caliber handgun will be sufficient for most horses. The use of hollow-point or soft nose bullets will increase brain destruction and reduce the chance of ricochet. If a shotgun is the only available firearm, the use of a rifled slug is preferred.
This method should only be attempted by individuals trained in the use of firearms and who understand the potential for ricochet. Care must be taken to minimize the danger to the operator, observers, and other animals. Personnel must comply with all laws and regulations governing the possession and discharge of firearms; local ordinances may prohibit the discharge of firearms in certain areas.