The wood the cabinet is made out of just 1x4 pine (select quality at Menards).
I put 3" drywall screws in the ends for extra strength - since this may end up having 50+ lbs of guns and related stuff inside it and hanging on the wall.
The screws did pull that gap down a bit, but I was careful and didn't go too far that it cracked. There is still a gap there, but the screws should secure it and also stop any movement that opening/closing the door does on that end. Fingers crossed that temp and humidity changes won't cause it to crack in the future. It will be in the house all the time.
The idea on this thing is a rustic look, which this crappy wood, gaps, dings, etc - lives up to the low expectations. I may paint the entire cabinet part (1x4) black down the road, or char it darker/black with the torch - like I did with the flag stripes.
You can see the unlocking magnet in the bottom picture, stuck to the lock.
Wow - woodnthings, you're at 23,999 posts above (when I'm looking at this anyway).
Here are a couple pictures of it almost complete. I only have to put the back on (1/8" pressed type wood/fiber board stuff) and the hanging hardware.
My son will have to cut out the foam for his guns to fit in it.