The Development of Armor-piercing Shells Part 4

Having described my invention what I claim is:

1. A projectile provided with a chamber extending along its length, the walls of said chamber being provided with longitudinal ribs extending in a spiral direction from the base of the chamber to the forward end thereof.

2. A projectile provided with a chamber extending along its length, the forward end of said chamber being pointed, the walls of said chamber being provided with longitudinal ribs extending in a spiral direction from the base of the chamber to the point thereof.

3. A projectile having the fibers of its material twisted in a spiral direction from the base of said projectile to the end thereof.

4. A projectile having the fibers of its material twisted in a spiral direction from the base of said projectile to the end thereof, said projectile having a central chamber, the walls of which are provided with longitudinal ribs extending in a spiral direction from the base of the chamber to the point thereof.

In testimony whereof, I have signed my name to this specification in the presence of two subscribing witnesses, this sixth day of December, 1906.

CARLOS DE ZAFRA.

Witnesses:

EMILO BELARI, EMMA RODERICK.

Bibliography

ORDNANCE AND GUNNERY BRUFF

TEST BOOK OF ORDNANCE AND GUNNERY INGERSOLL

REPORT ON THE ART OF WAR IN EUROPE--1854-1855-1856 COL. R. DELAFIELD, U.S.A.

JOURNAL OF THE U.S. ARTILLERY

THE SCIENTIFIC AMERICAN

SPECIFICATIONS OF THE BUREAU OF ORDNANCE, U.S. NAVY DEPARTMENT

SPECIFICATIONS OF THE ORDNANCE DEPARTMENT, U.S. ARMY

[Ill.u.s.tration: The de Zafra Improved Armor-Piercing Sh.e.l.l]