This is an example of a projectile and sabot assembly - in this case, a 12.7-mm stainless steel ball in a sabot for the 20-mm gun. The left-hand pane shows how the assembly looks when it's inserted into the barrel; the black o-ring (which is a little hard to see here) is there to hold everything together until the assembly is safely in the barrel. The two panes on the right show two different views of the sabot as it might fly apart after it leaves the barrel. Only the sphere should impact the target.

We typically use four-piece sabots. We make them from plastic stock, which comes in four pieces that can be fitted together to make a cylinder. Because the stock is much too long and doesn't have the right diameter for the barrels of our guns, we have to machine it to fit correctly. Four pieces of the sabot stock are put together and inserted into the lathe, after which Bill or Gerry turns them down to the correct diameter for the gun into which it'll be loaded. A hole is drilled into the front to accept the projectile, an o-ring (a rubberized plastic ring) is placed around the four pieces to keep them together, and the amount of sabot needed is then cut from the long stock. Voilá! A sabot.

The projectile is inserted into the hole in the front of the sabot before the sabot/projectile assembly is loaded into the barrel of the gun. The o-ring slides off when the sabot is inserted into the barrel, and the rest of the operation to prepare the gun for firing can then continue. When the gun is fired, the sabot/projectile assembly leaves the muzzle, but the spin caused by the rifling in the barrel causes the sabot to separate quickly from the projectile. The projectile passes through a hole in a solid piece of steel, while the four pieces of sabot, thrown away from the flight path of the projectile, hit the steel and are taken out of the picture in a burst of glory. If everything goes well, only the projectile goes through the hole. We have had shots in which, for one reason or another, a piece of the sabot hit near the hole and ended up downrange, where it wasn't supposed to be. When it's traveling so fast, even plastic can do a lot of damage, and we sometimes have to repeat a shot when this happens. Thankfully it isn't often.