The lock is only as secure as the precautions you take to protect the key or combination. Barrel lock This device typically works by looping a high-strength steel cable and a blocking piece of metal through the barrel of the gun. The device locks, sometimes through the trigger guard, with either a combination or a key lock. However, a hacksaw or a cable and bolt cutter can be used to sever the cable and disable the lock. As with the trigger lock, poor security with respect to key or combination can render the lock useless.
Barrel locks are somewhat more expensive than a trigger lock.
Cable locks will be distributed through local law enforcement in participating states. See the Project HomeSafe site for participating cities. Smart guns Research is proceeding to develop weapons that will reliably respond only to a programmed owner's identity through a thumbprint, palm print, specially encoded ring, or similar owner-recognition mechanisms. The theory is that these weapons will be inoperable by anyone except their legitimate owners and will therefore be unusable by criminals or by children and youth who might find them or seek them out. These weapons should still be stored unloaded and locked.