diff --git a/data/json/items/ammo/8x40mm.json b/data/json/items/ammo/8x40mm.json
index 21caacd7b3418..7047f5442e597 100644
--- a/data/json/items/ammo/8x40mm.json
+++ b/data/json/items/ammo/8x40mm.json
@@ -17,11 +17,11 @@
     "ascii_picture": "8mm_caseless",
     "description": "An 8x40mm caseless round.  Proprietary ammunition for Rivtech firearms.",
     "weight": "12 g",
-    "volume": "230 ml",
+    "volume": "150 ml",
     "price": 225,
     "price_postapoc": 8000,
     "flags": [ "IRREPLACEABLE_CONSUMABLE", "CASELESS_ROUNDS" ],
-    "material": [ "plastic", "powder" ],
+    "material": [ { "type": "steel", "portion": 33 }, { "type": "plastic", "portion": 50 }, { "type": "powder", "portion": 17 } ],
     "symbol": "=",
     "color": "pink",
     "count": 40,
diff --git a/data/mods/TEST_DATA/known_bad_density.json b/data/mods/TEST_DATA/known_bad_density.json
index 7b3e84cbd76b2..da4cfc9ca8fe6 100644
--- a/data/mods/TEST_DATA/known_bad_density.json
+++ b/data/mods/TEST_DATA/known_bad_density.json
@@ -2,7 +2,6 @@
   {
     "type": "test_data",
     "known_bad": [
-      "8mm_inc",
       "meal_chitin_piece",
       "blood",
       "curry_meat",
@@ -40,7 +39,6 @@
       "bot_gasbomb_hack",
       "sandwich_reuben_wheat_free",
       "tailoring_pattern_set",
-      "8mm_jhp",
       "young_koji",
       "k_gambeson_vest_xs",
       "candy2",
@@ -76,7 +74,6 @@
       "yeast",
       "alloy_plate",
       "candy3",
-      "kevlar_chainmail_suit",
       "a180mag4",
       "bolt_makeshift",
       "liquid_soap",
@@ -90,7 +87,6 @@
       "material_zincite",
       "small_lcd_screen",
       "biscuit",
-      "xl_kevlar_chainmail_hauberk",
       "koji",
       "light_minus_disposable_cell",
       "fire_piston",
@@ -241,7 +237,6 @@
       "pumpkin_yeast_bread",
       "bandages",
       "dried_salad",
-      "8mm_caseless",
       "lung_provence",
       "portal",
       "dandelion_tea",
@@ -250,7 +245,6 @@
       "bamboo_cooked",
       "throwing_stick",
       "cookbook_sushi",
-      "xl_kevlar_chainmail_suit",
       "willowbark",
       "soap",
       "young_yeast",
@@ -302,7 +296,6 @@
       "xl_k_gambeson_loose",
       "mre_accessory",
       "candy3gator",
-      "kevlar_chainmail_suit_xs",
       "bolt_simple_small_game",
       "raw_bamboo",
       "brew_whiskey",
@@ -385,7 +378,6 @@
       "human_cracklins",
       "acid_spray",
       "protein_powder",
-      "8mm_bootleg",
       "hellfire_stew",
       "large_stomach_sealed",
       "book_nonf_hard_dodge_tlwd",
@@ -440,7 +432,6 @@
       "hardtack",
       "textbook_arthropod",
       "vitamins",
-      "chem_match_head_powder",
       "unfinished_charcoal",
       "con_milk",
       "venom_paralytic",
@@ -487,7 +478,6 @@
       "pistachio",
       "nachosvc",
       "mortar_build",
-      "inj_vitb",
       "clay_lump",
       "manual_cutting",
       "pepto",
@@ -502,7 +492,6 @@
       "migo_bio_gun",
       "cannonball_4lb",
       "test_weldtank",
-      "8mm_civilian",
       "chem_glycerol",
       "xl_k_gambeson_pants",
       "test_gum",
@@ -555,7 +544,6 @@
       "amplifier_head",
       "sarcophagus_access_code",
       "mutant_blood",
-      "8mm_fmj",
       "chestnut",
       "flintlock_shot",
       "xedra_microphone",
@@ -590,7 +578,6 @@
       "flavored_bonemeal_tablet",
       "chaw",
       "moisturizer",
-      "8mm_hvp",
       "load_bearing_vest",
       "deluxe_beansnrice",
       "broken_lab_security_drone_GR",
@@ -708,7 +695,6 @@
       "porkbelly",
       "huge_atomic_battery_cell",
       "airhorn",
-      "kevlar_chainmail_hauberk_xs",
       "corpse_scorched",
       "mortar_adobe",
       "chilidogs_wheat_free",
@@ -727,7 +713,6 @@
       "soapy_water",
       "camera_control",
       "material_quicklime",
-      "kevlar_chainmail_hauberk",
       "art_urchin",
       "meat_fried",
       "k_gambeson",