When a bullet hits a protective material, the best defense depends on the round’s velocity and design. For rifle rounds, hard ceramic plates like silicon carbide or boron carbide are most effective, while for handgun rounds, flexible fabrics made of aramid fibers or UHMWPE provide the best protection.
Hard armor for rifle rounds
Ceramic plates are the standard for stopping high‑velocity rifle ammunition. Their extreme hardness erodes the projectile tip, causing it to fragment and lose energy before the backing material absorbs the remainder.
- Silicon carbide (SiC) offers a good balance of hardness and toughness.
- Boron carbide (B4C) is one of the hardest materials available, giving the highest stopping power.
- Alumina (Al2O3) is also used but is less hard than SiC or B4C.
Soft armor for handgun rounds
Flexible fabrics made from aramid fibers or ultra‑high‑molecular‑weight polyethylene (UHMWPE) are the most common choices for handgun protection. They absorb energy by stretching and distributing force across many fibers.
- Kevlar (an aramid fiber) is lightweight and has a high tensile strength.
- UHMWPE (brands such as Dyneema or Spectra) is even lighter and resists moisture and UV better.
- Both materials are effective against standard handgun bullets but not against rifle rounds.
Steel and titanium plates
Ballistic steels and titanium alloys provide solid protection against a wide range of threats. They rely on hardness and ductility to deform the bullet rather than shatter it.
- Steel plates can take multiple hits before failing.
- They are heavier than ceramic or polyethylene plates.
- Special coatings can reduce spalling, where fragments ricochet off the plate.
Choosing the right material
Selection depends on the threat level, weight tolerance, and desired flexibility. Ceramics are best for high‑velocity rifle rounds, while aramid fibers and UHMWPE suit handgun scenarios. Steel offers a middle ground with good multi‑hit performance but heavier weight.