 The first metal barrels were not designed to withstand high-nitrate gunpowder and a bore-filling projectile; rather, they were designed for the low-nitrate flamethrower fire lance that shot small coviative missiles.This was called the "bandit-striking penetrating gun" (ji zei bian chong).Some of these low–nitrate gunpowder flamethrowers used poisonous mixtures such as arsenious oxide, and would blast a spray of porcelain shards as fragmentation.