22-caliber semi-automatic rifle loaded with hollow-point cartridges.223-caliber bolt-action rifle with scope Two sawed-off double-barrel shotguns Rubino also owned silencers, an assault rifle ...

This refers to the the bullet's hollow-point tip that passes through barriers ... they're looking for up to 175 million rounds of .223 caliber ammo to be exact. The .223 is almost exactly the ...