Mil-A-46100D 1986

MILITARY SPECIFICATON ARMOR PLATE, STEEL, WROUGHT, HIGH HARDNESS

1. 1.1.This specification covers quenched and tempered high-hardness wrought steel armour plate for lightweight armour applications for recommended thickness up to 2 inches inclusive.

TABLE VI. Thickness ranges and corresponding test projectiles for first article testing (a).

Nominal thickness range (inches)	Obliquity (degrees)	Test Projectile
(a) Minimum required ballistic limits are tabulated in tables VII through X of the Appendix. The plates are tested at 30° obliquity.
0.125 to 0.300 incl.	30	Cal .30 AP, M2
0.301 to 0.590 incl.	30	Cal .50 AP, M2
0.591 to 0.765 incl.	30	14.5 mm API, B32
0.766 to 1.065 incl.	30	14.5 mm API, BS41
1.066 to 2.000 incl.	0	20 mm API-T, M602

20. DEFINITIONS

1. 20.6 V50 protection ballistic limit, BL(P). The protection V50 ballistic limit is defined as the average of 6 fair impact velocities comprising the three lowest velocities resulting in complete penetration and the three highest velocities resulting in partial penetration. A maximum spread of 150 feet per second shall be permitted between the lowest and highest velocities employed in determination of ballistic limits. In only those cases where the lowest complete penetration velocity is lower than the highest parital penetration velocity by more than 150 fps will the ballistic limit be based on 10 velocities (the 5 lowest velocities that resulted in complete penetration and the 5 highest velocities that resulted in partial penetrations). When the 10 round excessive spread, ballistic limit is used, the velocity spread will be reduced to the lowest partical level (as close to 150 fps as possible). When a 10 round ballistic limit is used, this will be noted in all reports. The normal up and down firing method will be used in the determination of all BL(P)‘s, all velocities being corrected to striking velocity. In the event that the ballistic limit computed is less than 30 fps above the minimum required and if a gap (high partial penetration velocity below the low complete penetration velocity) of 30 fps or more exists, firing will continue as needed to reduce this gap to 25 fps or less. (This procedure will insure better evaluation of the steel when the ballistic limit is near the minimum required.)