diff --git a/src/aim/target_ui.rs b/src/aim/target_ui.rs
index de55ff1..e90ba78 100644
--- a/src/aim/target_ui.rs
+++ b/src/aim/target_ui.rs
@@ -153,6 +153,7 @@ fn sync(
             new_state = Some(BackpackHead {
                 head: head.0,
                 health: hp.health(),
+                ammo: 1.,
             });
         }
     }
diff --git a/src/backpack/mod.rs b/src/backpack/mod.rs
index 18d5dd4..bdfd3dc 100644
--- a/src/backpack/mod.rs
+++ b/src/backpack/mod.rs
@@ -5,16 +5,29 @@ use bevy::prelude::*;
 
 pub use backpack_ui::BackpackAction;
 
-#[derive(Clone, Copy, Debug, PartialEq)]
+#[derive(Clone, Copy, Debug, PartialEq, Reflect)]
 pub struct BackpackHead {
     pub head: usize,
     pub health: f32,
+    pub ammo: f32,
 }
 
 impl BackpackHead {
+    pub fn new(head: usize) -> Self {
+        Self {
+            head,
+            health: 1.0,
+            ammo: 1.0,
+        }
+    }
+
     pub fn damage(&self) -> f32 {
         1. - self.health
     }
+
+    pub fn ammo_used(&self) -> f32 {
+        1. - self.ammo
+    }
 }
 
 #[derive(Resource, Default)]
@@ -37,6 +50,7 @@ fn setup(mut commands: Commands) {
             .map(|i| BackpackHead {
                 head: i,
                 health: 1.,
+                ammo: 1.,
             })
             .collect(),
     });
diff --git a/src/heads_ui.rs b/src/heads_ui.rs
index 5f2079d..2385dd8 100644
--- a/src/heads_ui.rs
+++ b/src/heads_ui.rs
@@ -6,7 +6,7 @@ use crate::{
     sounds::PlaySound,
 };
 use bevy::prelude::*;
-use bevy_ui_gradients::{AngularColorStop, BackgroundGradient, ConicGradient, Position};
+use bevy_ui_gradients::{AngularColorStop, BackgroundGradient, ConicGradient, Gradient, Position};
 use std::f32::consts::PI;
 
 pub static HEAD_COUNT: usize = 18;
@@ -35,9 +35,10 @@ pub struct HeadsImages {
     pub heads: Vec<Handle<Image>>,
 }
 
-#[derive(Resource, Default)]
+#[derive(Resource, Default, Reflect)]
+#[reflect(Resource)]
 pub struct ActiveHeads {
-    heads: [Option<usize>; 5],
+    heads: [Option<BackpackHead>; 5],
     current_slot: usize,
 }
 
@@ -46,8 +47,13 @@ pub struct HeadChanged(pub usize);
 
 pub fn plugin(app: &mut App) {
     app.register_type::<HeadDamage>();
+    app.register_type::<ActiveHeads>();
+
     app.add_systems(OnEnter(GameState::Playing), setup);
-    app.add_systems(Update, update.run_if(in_state(GameState::Playing)));
+    app.add_systems(
+        Update,
+        (update, update_ammo, update_health).run_if(in_state(GameState::Playing)),
+    );
     app.add_observer(on_select_active_head);
     app.add_observer(on_swap_backpack);
 }
@@ -82,7 +88,13 @@ fn setup(mut commands: Commands, asset_server: Res<AssetServer>, assets: Res<UIA
     commands.insert_resource(HeadsImages { heads });
 
     commands.insert_resource(ActiveHeads {
-        heads: [Some(0), Some(3), Some(6), Some(8), Some(9)],
+        heads: [
+            Some(BackpackHead::new(0)),
+            Some(BackpackHead::new(3)),
+            Some(BackpackHead::new(6)),
+            Some(BackpackHead::new(8)),
+            Some(BackpackHead::new(9)),
+        ],
         current_slot: 0,
     });
 }
@@ -117,6 +129,7 @@ fn spawn_head_ui(
                 ImageNode::new(selector),
                 HeadSelector(head_slot),
             ));
+
             parent.spawn((
                 Node {
                     position_type: PositionType::Absolute,
@@ -125,12 +138,20 @@ fn spawn_head_ui(
                 ImageNode::new(bg),
             ));
             parent.spawn((
+                Name::new("head-icon"),
                 Node {
                     position_type: PositionType::Absolute,
-                    // width: Val::Px(66.0),
-                    // height: Val::Px(66.0),
                     ..default()
                 },
+                BorderRadius::all(Val::Px(9999.)),
+                BackgroundGradient::from(ConicGradient {
+                    stops: vec![
+                        AngularColorStop::new(Color::linear_rgba(0., 0., 0., 0.9), 0.),
+                        AngularColorStop::new(Color::linear_rgba(0., 0., 0., 0.9), PI * 1.5),
+                        AngularColorStop::new(Color::linear_rgba(0., 0., 0., 0.0), PI * 1.5),
+                    ],
+                    position: Position::CENTER,
+                }),
                 ImageNode::default(),
                 Visibility::Hidden,
                 HeadImage(head_slot),
@@ -140,16 +161,7 @@ fn spawn_head_ui(
                     position_type: PositionType::Absolute,
                     ..default()
                 },
-                BorderRadius::all(Val::Px(9999.)),
                 ImageNode::new(regular),
-                BackgroundGradient::from(ConicGradient {
-                    stops: vec![
-                        AngularColorStop::new(Color::linear_rgba(0., 0., 0., 0.9), 0.),
-                        AngularColorStop::new(Color::linear_rgba(0., 0., 0., 0.9), PI * 1.5),
-                        AngularColorStop::new(Color::linear_rgba(0., 0., 0., 0.0), PI * 1.5),
-                    ],
-                    position: Position::CENTER,
-                }),
             ));
             parent
                 .spawn((Node {
@@ -187,7 +199,7 @@ fn update(
         for (HeadImage(head), mut vis, mut image) in head_image.iter_mut() {
             if let Some(head) = res.heads[*head] {
                 *vis = Visibility::Visible;
-                image.image = heads_images.heads[head].clone();
+                image.image = heads_images.heads[head.head].clone();
             } else {
                 *vis = Visibility::Hidden;
             }
@@ -202,6 +214,31 @@ fn update(
     }
 }
 
+fn update_ammo(res: Res<ActiveHeads>, mut gradients: Query<(&mut BackgroundGradient, &HeadImage)>) {
+    if res.is_changed() {
+        for (mut gradient, HeadImage(head)) in gradients.iter_mut() {
+            if let Some(head) = res.heads[*head] {
+                let ammo_used = head.ammo_used();
+                let Gradient::Conic(gradient) = &mut gradient.0[0] else {
+                    continue;
+                };
+                let angle = PI * 2. * ammo_used;
+                gradient.stops[1].angle = Some(angle);
+                gradient.stops[2].angle = Some(angle);
+            }
+        }
+    }
+}
+
+fn update_health(res: Res<ActiveHeads>, mut query: Query<(&mut Node, &HeadDamage)>) {
+    if res.is_changed() {
+        for (mut node, HeadDamage(head)) in query.iter_mut() {
+            node.height =
+                Val::Percent(res.heads[*head].map(|head| head.damage()).unwrap_or(0.) * 100.);
+        }
+    }
+}
+
 fn on_select_active_head(
     trigger: Trigger<SelectActiveHead>,
     mut commands: Commands,
@@ -217,7 +254,7 @@ fn on_select_active_head(
     }
 
     commands.trigger(PlaySound::Selection);
-    commands.trigger(HeadChanged(res.heads[res.current_slot].unwrap()));
+    commands.trigger(HeadChanged(res.heads[res.current_slot].unwrap().head));
 }
 
 fn on_swap_backpack(
@@ -233,16 +270,13 @@ fn on_swap_backpack(
     let current_active_slot = res.current_slot;
 
     let current_active_head = res.heads[current_active_slot];
-    res.heads[current_active_slot] = Some(head.head);
+    res.heads[current_active_slot] = Some(*head);
 
     if let Some(old_active) = current_active_head {
-        backpack.heads[backpack_slot] = BackpackHead {
-            head: old_active,
-            health: 1.,
-        };
+        backpack.heads[backpack_slot] = old_active;
     } else {
         backpack.heads.remove(backpack_slot);
     }
 
-    commands.trigger(HeadChanged(res.heads[res.current_slot].unwrap()));
+    commands.trigger(HeadChanged(res.heads[res.current_slot].unwrap().head));
 }