Fix seemingly erroneous json entries

data/json/items/gun/9mm.json

@@ -321,7 +321,7 @@
     "material": [ "steel", "plastic" ],
     "symbol": "(",
     "color": "dark_gray",
-    "ammo": "9mm",
+    "ammo": [ "9mm", "460" ],
     "range": 1,
     "dispersion": 340,
     "durability": 9,

data/mods/Generic_Guns/firearms/pistol_tiny.json

@@ -6,7 +6,8 @@
     "name": "plinker carbine",
     "ammo": "ammo_pistol_tiny",
     "description": "With near non-existent recoil and inexpensive ammunition, rifles like this one are popular introductory firearms.  It has a built in magazine, capable of holding an impressive amount of its small cartridges.  You could take small game with this, but anything bigger might not even notice.",
-    "clip_size": 19
+    "clip_size": 19,
+    "magazines": [  ]
   },
   {
     "id": "pistol_tiny_target",

data/mods/Generic_Guns/firearms/rifle.json

@@ -24,7 +24,8 @@
     "name": "pipe rifle",
     "ammo": "ammo_rifle",
     "description": "A crude longarm chambered in standard rifle ammunition, reinforced near the chamber.  It holds a single a round and has a crude assembly to fire it.  There's no extractor, so it might be slow to reload, and its construction makes for poor reliability and longevity.",
-    "clip_size": 1
+    "clip_size": 1,
+    "magazines": [  ]
   },
   {
     "id": "rifle_pipe_carbine",

data/mods/Generic_Guns/magazines/gg_magazines_migration.json

@@ -19,6 +19,8 @@
       "hptcf380mag_10rd",
       "taurus_spectrum_mag",
       "m1911mag_10rd_38super",
+      "m9mag",
+      "makarovmag",
       "glock40mag",
       "sig40mag",
       "bhp40mag",
@@ -57,11 +59,6 @@
     "type": "MIGRATION",
     "replace": "pistol_magnum_mag"
   },
-  {
-    "id": [ "m9mag", "makarovmag" ],
-    "type": "MIGRATION",
-    "replace": "pistol_medium"
-  },
   {
     "id": [
       "20x66_40_mag",