What’s the difference between pistol and rifle powder? It’s the difference between having a nice working AR-15 and one that is blown to Hell and back again. The shooter was lucky and ended up walking away from this with all his digits still firmly attached to his hands which are still firmly attached to his arms.
Reloading can be dangerous if you aren’t giving 100% of your attention to what you’re doing. It never hurts to triple check everything before you crank out some ammunition.