Welcome to the site. I have built my own gun cabnit but no plans. Just played it by ear. I like cabnits better than safes, seems this country is in one hell of an uproar over everything anymore. I took a different attitude and taught my kids about guns. Would send you a photo but haven't re-done it yet since my house burned.
Just keep in mind, your building a box to keep your guns in. Take it from there.
Others have offered up a sighting of roughly 2 inches high at 100 yards as a good sighting scheme. In my own experience I have come to favor a sighting of 3.5 inches high at 100 yards. This allows for the individual to hold dead-on (directly in the middle of the top and bottom) the animal out to roughly 350 yards.
Magnum calibers such as the 7mm Remington and 300 Winchester will extend this slightly. At 400 yards I hold directly on the backbone of the animal. The drop at this range allows the...