diff --git a/server/gameserver/bullet.cc b/server/gameserver/bullet.cc
index 9db7baf9..1554ccb0 100644
--- a/server/gameserver/bullet.cc
+++ b/server/gameserver/bullet.cc
@@ -732,10 +732,10 @@ void Bullet::GetHitThings(BulletCheckResult& result)
                          sender.Get()->team_id == ob->GetTeamId(room)) {
                          bool ret = Collision::Check2dRotationRectangle
                              (GetPos().x,
-                              GetPos().y,
+                              GetPos().z,
                               gun_meta->bullet_rad(),
                               ob->GetPos().x,
-                              ob->GetPos().y,
+                              ob->GetPos().z,
                               ob->meta->width(),
                               ob->meta->height(),
                               ob->GetRotate() * 180.0f