Yes, that’s how it goes. But ammonium nitrate/ANFO (the fuel oil/diesel is mixed with it in order to sensitize it marginally, or rather to give a medium for the initiating shockwave to propagate through) has the extra special distinction of not being brisant enough to be self-propagating. Unlike dynamite, TNT, RDX/C4, etc., you need to have an initiator big enough to encapsulate your entire ammonium nitrate payload in a shockwave that’s powerful enough to set it off. That’s pretty tough for a home gamer to do.