The Ohio Revised Code is the law. You don't need to worry about local laws in Ohio as the state law preempts them when it comes to firearms.
Ohio is an open carry state. You could if you wanted, keep the gun loaded and holstered in plain view during your walk. Without a CCL you can not have a loaded handgun in your car or on your person. As you noted a loaded magazine or speed-loader equals a loaded gun in Ohio.
I would not suggest just dropping the pistol in the pack and using Velcro to keep it closed. If your backpack has zippers I'd suggest using a small padlock to lock the bag. A trigger or cable lock would not be a bad idea if you don't have a lockable case to transport the pistol.
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NRA RSO & Certified Instructor in rifle, pistol, shotgun.
An unloaded pistol is a paperweight.
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