I'd pull the bullets. Collect the powder in a container. I'd first try selling the bullets and brass on a local online want ads (we have a very good one here) or take them to a metal recycler. The powder, I'd dump on my driveway and touch a match to (it does not explode, it burns, and is kind of fun to watch) and if you are not comfortable with that, sprinkle it around the yard as fertilizer.