diff --git a/src/main/java/cactusServer/models/CollisionManager.java b/src/main/java/cactusServer/models/CollisionManager.java
index e1bb494..c3a37c9 100644
--- a/src/main/java/cactusServer/models/CollisionManager.java
+++ b/src/main/java/cactusServer/models/CollisionManager.java
@@ -44,8 +44,8 @@
 		for (String instanceId : instances.keySet()) {
 			Instance instance = Instances.getInstance().getInstance(instanceId);
 			instance.getUniverse().update(interval);
-			collisionPlayersObjects(instanceId, instance);
-			// collisionBulletsAndOthers(instanceId, instance);
+			collisionPlayersObjects(instanceId, instance);
+			collisionBulletsAndOthers(instanceId, instance);
 		}
 	}
 
@@ -92,80 +92,54 @@
 		vec.add(result.normal);
 		object.setPosition(new Position3D(vec));
 	}
-
-	// private void collisionBulletsAndOthers(String instanceId, Instance instance)
-	// {
-	// System.out.println("a");
-	// for (Map.Entry<String, HashMap<String, Bullet>> playersBulletsEntry :
-	// instance.getBullets().entrySet()) {
-	// String bulletOwnerPlayerId = playersBulletsEntry.getKey();
-	// Map<String, Bullet> bulletMap = playersBulletsEntry.getValue();
-	// for (Map.Entry<String, Bullet> bulletEntry : bulletMap.entrySet()) {
-	// String bulletId = bulletEntry.getKey();
-	// Bullet bullet = bulletEntry.getValue();
-	// System.out.println("b");
-	// collisionBulletAndPlayers(instanceId, instance, bulletOwnerPlayerId,
-	// bulletId, bullet);
-	// System.out.println("c");
-	// collisionBulletAndObjects(instance, bulletOwnerPlayerId, bulletId, bullet);
-	// System.out.println("d");
-	// }
-	// }
-	// }
-
-	private void collisionBulletsAndOthers(String instanceId, Instance instance) {
-		System.out.println("a");
-		// for (Map.Entry<String, HashMap<String, Bullet>> playersBulletsEntry :
-		// instance.getBullets().entrySet()) {
-		Iterator<Map.Entry<String, HashMap<String, Bullet>>> playersBulletsEntryIt = instance.getBullets().entrySet()
-				.iterator();
+
+	private void collisionBulletsAndOthers(String instanceId, Instance instance) {
+		Iterator<Map.Entry<String, HashMap<String, Bullet>>> playersBulletsEntryIt = instance.getBullets().entrySet().iterator();
 		while (playersBulletsEntryIt.hasNext()) {
 			Map.Entry<String, HashMap<String, Bullet>> playersBulletsEntry = playersBulletsEntryIt.next();
 			String bulletOwnerPlayerId = playersBulletsEntry.getKey();
-			Map<String, Bullet> bulletMap = playersBulletsEntry.getValue();
-			// for (Map.Entry<String, Bullet> bulletEntry : bulletMap.entrySet()) {
+			Map<String, Bullet> bulletMap = playersBulletsEntry.getValue();
 			Iterator<Map.Entry<String, Bullet>> bulletEntryIt = bulletMap.entrySet().iterator();
 			while (bulletEntryIt.hasNext()) {
 				Map.Entry<String, Bullet> bulletEntry = bulletEntryIt.next();
 				String bulletId = bulletEntry.getKey();
 				Bullet bullet = bulletEntry.getValue();
-				System.out.println("b");
-				collisionBulletAndPlayers(instanceId, instance, bulletOwnerPlayerId, bulletId, bullet, bulletEntryIt);
-				System.out.println("c");
-				collisionBulletAndObjects(instance, bulletOwnerPlayerId, bulletId, bullet, bulletEntryIt);
-				System.out.println("d");
+				boolean isRemoved = collisionBulletAndPlayers(instanceId, instance, bulletOwnerPlayerId, bulletId, bullet, bulletEntryIt);
+				if (!isRemoved) {
+					collisionBulletAndObjects(instance, bulletOwnerPlayerId, bulletId, bullet, bulletEntryIt);
+				}
 			}
 		}
-	}
-
-	private void collisionBulletAndPlayers(String instanceId, Instance instance, String bulletOwnerPlayerId,
+	}
+	private boolean collisionBulletAndPlayers(String instanceId, Instance instance, String bulletOwnerPlayerId,
 			String bulletId, Bullet bullet, Iterator<Map.Entry<String, Bullet>> bulletEntryIt) {
 		Instances instances = Instances.getInstance();
 		for (Map.Entry<String, Player> playersEntry : instances.getPlayers(instanceId).entrySet()) {
 			if (isCollision(bullet, playersEntry.getValue())) {
 				if (!(playersEntry.getKey().equals(bulletOwnerPlayerId))) {
 					// Player(����������)�ƒe�������������̏���������
-				}
-				// instance.destroyBullet(bulletOwnerPlayerId, bulletId); //
+				}
 				// Player(�������܂�)�ɓ��������e������
-				bulletEntryIt.remove();
-				instance.getUniverse().displace(bullet.getPlaceable());
+//				bulletEntryIt.remove(); 
+//				instance.getUniverse().displace(bullet.getPlaceable());
+//				System.out.println(bulletId + "�폜");
+				return true;
 			}
 		}
+		return false;
 	}
-
-	private void collisionBulletAndObjects(Instance instance, String bulletOwnerPlayerId, String bulletId,
-			Bullet bullet, Iterator<Map.Entry<String, Bullet>> bulletEntryIt) {
-		System.out.println("c1");
+
+	private boolean collisionBulletAndObjects(Instance instance, String bulletOwnerPlayerId, String bulletId,
+			Bullet bullet, Iterator<Map.Entry<String, Bullet>> bulletEntryIt) {
 		for (MovableObject object : instance.getObjects().values()) {
-			if (isCollision(bullet, object)) {
-				System.out.println("c2");
-				// instance.destroyBullet(bulletOwnerPlayerId, bulletId);
-				bulletEntryIt.remove();
-				instance.getUniverse().displace(bullet.getPlaceable());
-				System.out.println("c3");
+			if (isCollision(bullet, object)) {
+//				bulletEntryIt.remove();
+//				instance.getUniverse().displace(bullet.getPlaceable());
+//				System.out.println(bulletId + "�폜");
+				return true;
 			}
 		}
+		return false;
 	}
 
 	private boolean isCollision(Bullet bullet, Player player) {