manta49, if done voluntarily, it's "responsible ownership."
If mandated by the government, it is gun control.
If government can dictate that guns must be stored, then government can dictate:
1) a minimum thickness, weight, and other specifications for a storage device - this could potentially be cost-prohibitive for many people, and an anti jurisdiction could deliberately set standards that typical citizens could not afford;
2) that ALL guns must be stored - there is a lawsuit going on in California, IIRC, about a city requiring gun owners to lock up all guns at night, and the plaintiff arguing that he might not have time to unlock and load his nightstand gun in the event of a break-in;
3) criminal penalties for failure to meet arbitrary standards.
That's all gun control, by any other name.