Perforation Limits for Nonshattering Projectile against Thick Homogeneous Armor at Normal Incidence
Abstract
Using unjacketed caliber .244 projectiles that did not shatter, limit energies have ben determined at normal incidence for homogeneous armor (BHN 255) ranging in thickness from 0.24 to 6 calibers. For plates over 1.5 calibers thick, the data have been correlated by means of an empirical equation of the form (WV (expn 2) / d (expn 3)) = R (e /d) (expn n), where W is the weight of the projectile, V is limit velocity; R is a measure of the "strength" of the plate material and has units of force per unit area, e is the plate thickness, d is the diameter of the projectile, and n is a constant. With a particular ptojectile and plate of a given thickness, R and n are constant, but they vary with changes in the plate and projectile parameters. (1) R and n are independent of the mass of the projectile only for thick plate (> 1.5 calibers). For thinner plate the limit energy was found to increase with increase in mass. (2) For projectiles of conventional nose shape n has a nominal value near 1.25 (less than the value usually used in De Marre formula). Changes in shape produce slight variations in both R and n. As the nose becomes sharper R and n decrease. (3) There is an indication that a "scale effect" causes a small decrease in R with an increase in the caliber of the projectile. (4) As expected, R incrased with an incrase in plate hardness.
Document Details
- Document Type
- Technical Report
- Publication Date
- Dec 01, 1945
- Accession Number
- ADA953510
Entities
People
- Christopher W. Curtis
- R. L. Kramer
Organizations
- Princeton University