Light Body Armor
Reports from American Headquarters in France indicated the need of producing a body armor which would protect the front and back alike and which was of such a weight that it could be carried by an infantryman with minimum discomfort. Trials had earlier been made with several types of British body shields but they had proved unsatisfactory.
For the new defense a maximum weight of seven or eight pounds was recommended. A body armor which was aimed at meeting this requirement was produced by the engineering Division of the Ordinance Department. This defense consisted of a plastron which was attached to the blackplate by means of shoulder straps; these terminated in metal plates having openings like keyholes which fitted to pegs on the breastplate. The breastplate was formed of three plates held together by leather strips, to the lowest of which was laced a "sporran plate" protecting the groin. Between each pair of plates a small piece of leather was inserted attached by the same rivets which held the plates together on the back of the breastplate. These aimed to prevent rattling when the breastplate was worn.
The present defense covered the front of the body of the wearer quite completely and its size was so arranged that it could be worn by men of various heights and weights. In the case of a man of short stature, it might be worn without the sporran plate. In molding the uppermost element of this breastplate care was taken to allow considerable latitude for the movements of the shoulders and arms of the wearer; thus, space was given, especially on the right side, to enable the infantryman to use his rifle.
A cushioning was arranged within this breastplate in the form of a sponge-rubber pad nearly one inch in thickness. This kept the uppermost part of the defense at a sufficient distance from the body of the wearer to render him safe from an injury which might be caused by the indentation of the plate. This cushion was vulcanized to the metal by means of a new process, the so called "acid cure," wherein it is not necessary to heat the metal and run the risk of drawing its temper. The metal used for this defense was manganese steel .036 inch to .040 inch in thickness. Its ballistic test showed that it would uniformly resist penetration of revolver ammunition at 850 foot seconds.
Such a defense would render the wearer reasonably immune to shrapnel, splinters, spent balls, and even to rifle fire, in case the bullet impinged at a considerable angle. The backplate accompanying the foregoing defense is also laminated; it is made up of a large upper plate, two intermediate pieces, and a lowermost plate or garde reins. These elements are riveted together and made inter flexible by the way of slotted grooves in which the rivets can travel as in the old-fashioned "alemayne rivets." The backplate like the breastplate is designed to suit wearers of many sizes and to be worn with a considerable degree of comfort. It is cushioned with sponge rubber which protects the wearer against injuries caused by the indentation of the metal.
The backplate is provided with belt straps which pass between the breatplate and the main leather straps, holding together the wide plates of this defense. A second type of backplate is shown in Fig. 199 and 200. This modeled in a single piece and so designed that it will fit backs of various sizes. It can be worn comfortably under the pack, if need be, and furnishes a considerable degree of protection. Like the former backplate it is made of manganese steel .036 inch to .040 inch in thickness and is not penetrated by service ammunition of the automatic revolver at 850 foot seconds. We note that with the experimental lot here described some of the breastplates were furnished with shoulder plates similar to those seen in Figs 189 or 192 but of greater length. These could be so molded by the wearer that they would lie close to his shoulder blade and help to keep the defense in position without further attachment.
There can be no question, however, that the corselets provided with the type of shoulder plates shown in Fig 196 are the better from the the armorr's point of view, since the other type of attachment did not prevent the breasteplate from "hiking up" or from becoming detached in case the wearer threw himself on the ground or even when he made certain movements in bending. The present defense weight, front and back together, eight and one half pounds.