Posted On: 10/20/11
A: Birdshot is intended to kill birds and break clay pigeons, not penetrate deep enough into the body of a violent attacker to rapidly and reliably stop them from threatening you. If you are going to use a shotgun for self defense, choose buckshot or slugs, not birdshot.
Posted On: 9/28/11
A: Your friend's shotgun might need to have the hammer spring replaced or other internal components inspected. What was most likely happening is that the Winchester primers are slightly harder, and require more force to ignite. The Federal primers might be slightly softer. As for shot size, #9 shot is smaller than #7 and therefore each shell will have more individual lead shot "pellets" by quantity. For skeet and trap, this might come in handy; for hunting upland game, a "lower" number like 7 shot will provide cleaner kills.