Yeah, I hear you but 1/4 inch is not bulletproof. Its like saying "ballistics grade sand". Which in sufficient thicknesses, is bulletproof =D.
"MIL-DTL-46027 is supplied as a 5083-H131 product. Ballistic reports are supplied for thicknesses over 0.499" per specification. Our stock range is 0.250" thru 3". Typical stock size is 72" wide x 144" long."
"MIL-DTL-46027 is supplied as a 5083-H131 product. Ballistic reports are supplied for thicknesses over 0.499" per specification. Our stock range is 0.250" thru 3". Typical stock size is 72" wide x 144" long."
Similar qualification for
MIL-DTL-46063 REV H OR LATEST
http://www.cliftonsteel.com/aluminum-armor-plate.html