Even when the stunner has been serviced correctly, the machined cylinder bore eventually wears out and the stunner will lose hitting power. At this point the stunner will have to be replaced. Poor ergonomics of bulky pneumatic stunners. Adding additional handlers will aid positioning. When a pneumatic stunner is used with a conveyor restrainer it is often easier to position it if it is hung from the balancer on a 30 degree angle.
Stunner operator chases the animal's head.
The operator should be trained to wait for the animal to stop moving and then position the stunner. Chasing the head will result in poor stunning. Careful quiet handling and driving of animals into the stun box or restrainer will provide calm animals that are easier to stun correctly. Air pressure too low to power a pneumatic stunner. Use the air pressure setting recommended by the manufacturer.