Bullet Resistant Glass

Bullet-resistant glass is a strong but optically transparent material that is cannot be penetrated when struck. However, they are not completely impenetrable.

Applications

  • Glass is brittle and it does not have a good orderly crystalline structure. If it did, it would be like metal steel, where it dents and deforms instead of shattering.
  • This allows the glass to absorb the bullet’s energy by transferring the kinetic energy of the bullet into shattering the glass.
  • The softer plastic layer reinforces the glass by holding it in place and allowing the glass to flex back as it absorbs the impact.
  • The polycarbonate and laminate also spread the force of the bullet laterally across the entire glass surface.
  • Layering these in multiple sheets allows the window to use properties of both materials more effectively; such as the glass on the backside shattering while the undamaged glass holds together the window. This also allows the glass to stop more that one bullet.
  • Since polycarbonate is very strong and does not shatter like glass it is an excellent candidate for bullet-proofing.

Bullet Resistance Classification According To European Norms EN 1063

RN – Round Nose SC – Soft Core (lead) AP – Armour Piercing FJ – Full Metal Jacket CB-Cone Bullet LB – Lead Bullet
SCP – Soft Core (lead) & Steel Penetrator API – Armour Piercing Incendiary FN – Flat Nose PB – Pointed Bullet HC – Hard core, steel hardness > 63 HRC

  Class Weapon Caliber Type Weight (g) Range (m) Velocity (m/s) Impact Energy Shots
BR1 Handgun/Rifle 0.22 LR LB/RN() 2.6 ± 0.1 10.00 ± 0.5 360 ± 10 170 J 3
BR2 Handgun 9×19mm Parabellum FJ/RN/SC 8.0 ± 0.1 5.00 ± 0.5 400 ± 10 640 J 3
1 1 1 1 1 1 1 1 1
BR3 Handgun 0.357 Magnum FJ/CB/SC 10.2 ± 0.1 5.00 ± 0.5 430 ± 10 940 J 3
BR5 Rifle 5.56×45mm NATO FJ/PB/SCP 4.0 ± 0.1 10.00 ± 0.5 950 ± 10 1800 J 3
BR6 Rifle 7.62×51mm NATO FJ/PB/SC 9.5 ± 0.1 10.00 ± 0.5 830 ± 10 3270 J 3
BR7 Rifle 7.62×51mm NATO FJ/PB/HC 9.8 ± 0.1 10.00 ± 0.5 820 ± 10 3290 J 3