diff --git a/technic/machines/HV/nuclear_reactor.lua b/technic/machines/HV/nuclear_reactor.lua
index c4587bb..b57faa7 100644
--- a/technic/machines/HV/nuclear_reactor.lua
+++ b/technic/machines/HV/nuclear_reactor.lua
@@ -259,7 +259,7 @@ minetest.register_node("technic:hv_nuclear_reactor_core", {
 	tiles = {"technic_hv_nuclear_reactor_core.png", "technic_hv_nuclear_reactor_core.png",
 	         "technic_hv_nuclear_reactor_core.png", "technic_hv_nuclear_reactor_core.png",
 	         "technic_hv_nuclear_reactor_core.png", "technic_hv_nuclear_reactor_core.png"},
-	groups = {snappy=2, choppy=2, oddly_breakable_by_hand=2, technic_machine=1},
+	groups = {cracky=1, technic_machine=1},
 	legacy_facedir_simple = true,
 	sounds = default.node_sound_wood_defaults(),
 	drawtype="nodebox",
@@ -293,7 +293,7 @@ minetest.register_node("technic:hv_nuclear_reactor_core_active", {
 	tiles = {"technic_hv_nuclear_reactor_core.png", "technic_hv_nuclear_reactor_core.png",
 	         "technic_hv_nuclear_reactor_core.png", "technic_hv_nuclear_reactor_core.png",
 		 "technic_hv_nuclear_reactor_core.png", "technic_hv_nuclear_reactor_core.png"},
-	groups = {snappy=2, choppy=2, oddly_breakable_by_hand=2, technic_machine=1, radioactive=7, not_in_creative_inventory=1},
+	groups = {cracky=1, technic_machine=1, radioactive=7, not_in_creative_inventory=1},
 	legacy_facedir_simple = true,
 	sounds = default.node_sound_wood_defaults(),
 	drop="technic:hv_nuclear_reactor_core",