Background: Results of an experimental study are given involving high-impact
ballistic tests using .22 inch diameter ammunition (commonly known only as .22 ammunition)
with the target set up as a combination of different numbers and weights of Kevlar layers.
These experimental tests are conducted as literature indicating that the .22 projectiles are
not as effective as with larger calibre ammunition. Present work is part of a research study to
assess the safety limits of Kevlar layers of different weights against various calibre projectiles.
Objective: The objective is to obtain test data to determine the number of Kevlar layers and
weights needed for the design of safe bullet proof vests capable of stopping various size
ammunition. In the present study, results are given for .22 inch ammunition, which provide
data on the characteristics of high-speed ballistic penetration of .22 bullets into Kevlar layers
and stopping distances in gel/Kevlar combinations.
Methods: Tests were performed with Kevlar fabrics of different weights of Gram per Square
Meter (GSM) to provide a comparison among different Kevlar fabrics as well as with different
number of Kevlar layers. The tests were conducted with the use of a chronograph in a
controlled test environment. The penetration depth in ballistic gelatine was recorded.
Results: The results identify the number of layers of Kevlar required to stop a .22 projectile
and the relationship between the different layers and weights of Kevlar materials. The results
of the .22 projectile penetration are compared with those of different 9 mm Parabellum
projectiles to assess the effect of different size ammunition on the bullet-proof capabilities of
Kevlar. Experimental data on the penetration depths of different types of bullets into the
gel/Kevlar combinations are presented using various graphs.
Conclusion: The .22 projectiles perform similar penetration depths compared to that of
9 mm projectiles, and therefore cannot be considered as ineffective ammunition as literature