The one thing I like to tell about Doom Beach when they ask how they sound is that they're loud. That's the single best word to use to describe them. It doesn't matter what song they're playing, their sound is just loud and will likely knock you on your ass if you're not ready for it.
I'm not sure who to compare Doom Beach with because there are so many elements coming into this sound. It's part punk, part hardcore, part metal, parts subgenres of those genres and even rock n roll at times. But it all just comes out to where the guitar and drums work so perfectly together and then just so loudly. Parts Refused, parts The Dedication, parts "Bleach" era Nirvana, parts "In Utero" era Nirvana and then just all of it coming together to hear some of the loudest music you will ever hear.
As I type this, I've seen Doom Beach several times live now and while this cassette is loud their live show is even more so. If you have the chance to see Doom Beach live, you definitely should to get the full experience of not being able to hear properly for a little bit. But until then, you can definitely play "Copperhead" at maximum volume because it's what your neighbors and parents would want.