This picture is a totally different caliber, but it is a good illustration:
A “cap” on a round is a solid piece shaped to help with armor penetration, but the shape is not good for flight. So a “ballistic cap” is staked on top of it. A hat on a hat, if you will. In the smaller photo in the illustration is a general idea of how these rounds look at a distance.
Ok, so then the real thing I’m learning here is that the shell is made out of the lighter, softer material to deliver the energy. They put the penetrator cap on, usually made of steel or some stronger heavier material, but it’s thin so not significantly decreasing shell velocity. However, the shape of the penetrator allows for the energy to be delivered all at one precise spot, but it causes the flight characteristics to suck. To get the flight back, they add a thin lightweight material back over the penetrator that is negligible in terms of reducing the energy the penetrator delivers.
The cap (the “penetrative cap” as the above picture calls it) protects the hardened tip of the shell itself, so that the tip doesn’t deform immediately on impact with armor. Soft metal caps did exist and work, but hard metal caps became more common since the hard cap would survive a little bit longer and thus get the shell better positioned to penetrate by the cap hopefully going through the outer layer of armor before the tip on the shell came forward to penetrate the remaining armor.
![[OC] Projectile ring for ammunition inside the 16 inch main gun of the USS North Carolina](https://lemmy.world/pictrs/image/b54e0d3c-047a-4cd3-b73f-aaaff9c09feb.jpeg){kind=link}
The pictured shells are solid bodied all the way to the top fuze threading. There’s no distinct ballistic cap, like with the below picture.
TIL. I always thought it was the opposite.
This picture is a totally different caliber, but it is a good illustration:
A “cap” on a round is a solid piece shaped to help with armor penetration, but the shape is not good for flight. So a “ballistic cap” is staked on top of it. A hat on a hat, if you will. In the smaller photo in the illustration is a general idea of how these rounds look at a distance.
Ahhh.
Ok, so then the real thing I’m learning here is that the shell is made out of the lighter, softer material to deliver the energy. They put the penetrator cap on, usually made of steel or some stronger heavier material, but it’s thin so not significantly decreasing shell velocity. However, the shape of the penetrator allows for the energy to be delivered all at one precise spot, but it causes the flight characteristics to suck. To get the flight back, they add a thin lightweight material back over the penetrator that is negligible in terms of reducing the energy the penetrator delivers.
Cool
Almost.
The cap (the “penetrative cap” as the above picture calls it) protects the hardened tip of the shell itself, so that the tip doesn’t deform immediately on impact with armor. Soft metal caps did exist and work, but hard metal caps became more common since the hard cap would survive a little bit longer and thus get the shell better positioned to penetrate by the cap hopefully going through the outer layer of armor before the tip on the shell came forward to penetrate the remaining armor.