This movie called Kichiku: Banquet of The Beast was goddamn gory as hell. Its these Japanese students who shoot each other, cut each other up. One scene they tie up a kid, shoot his head off with a shotgun and the chick inspects the head and brains like its a beautiful flower.
Cannibal Holocaust is pretty gory too. Especially when they rip that sea turtle open.
Lucio Fulci’s Zombi 2, The Beyond, City of The Living Dead have some great gore.
Carpenter’s The Thing has some nice gore.
I’ve seen a bunch, but I love gory movies, they are usually alot of fun to watch.