diff --git a/app/controllers/projects/git/base_controller.rb b/app/controllers/projects/git/base_controller.rb
index fbf60d44c..f8976c2d8 100644
--- a/app/controllers/projects/git/base_controller.rb
+++ b/app/controllers/projects/git/base_controller.rb
@@ -10,8 +10,7 @@ class Projects::Git::BaseController < Projects::BaseController
   protected
 
   def set_treeish_and_path
-    @treeish = params[:treeish].presence || @project.default_branch
-    @path = params[:path]
+    @treeish, @path = @project.default_head(params[:treeish]), params[:path]
   end
 
   def set_branch_and_tree
diff --git a/app/controllers/projects/pull_requests_controller.rb b/app/controllers/projects/pull_requests_controller.rb
index 63ce7cdc0..b0157df05 100644
--- a/app/controllers/projects/pull_requests_controller.rb
+++ b/app/controllers/projects/pull_requests_controller.rb
@@ -152,8 +152,8 @@ class Projects::PullRequestsController < Projects::BaseController
       @pull.issue.body = pull_params[:issue_attributes][:body].presence
     end
     @pull.from_project = @project
-    @pull.to_ref = (pull_params[:to_ref].presence if pull_params) || @pull.to_project.default_branch
-    @pull.from_ref = params[:treeish].presence || (pull_params[:from_ref].presence if pull_params) || @pull.from_project.default_branch
+    @pull.to_ref = (pull_params[:to_ref].presence if pull_params) || @pull.to_project.default_head(params[:treeish])
+    @pull.from_ref = params[:treeish].presence || (pull_params[:from_ref].presence if pull_params) || @pull.from_project.default_head(params[:treeish])
     @pull.from_project_owner_uname = @pull.from_project.owner.uname
     @pull.from_project_name = @pull.from_project.name
   end
diff --git a/app/models/project.rb b/app/models/project.rb
index b9a795d45..2f58f40e7 100644
--- a/app/models/project.rb
+++ b/app/models/project.rb
@@ -178,6 +178,14 @@ class Project < ActiveRecord::Base
     AbfWorker::BuildListsPublishTaskManager.destroy_project_from_repository self, repository
   end
 
+  def default_head treeish = nil # maybe need change 'head'?
+    if repo.branches_and_tags.map(&:name).include?(treeish || default_branch)
+      treeish
+    else
+      repo.branches_and_tags[0].try(:name) || 'master'
+    end
+  end
+
   protected
 
   def truncate_name
diff --git a/app/models/pull_request.rb b/app/models/pull_request.rb
index a67af1587..ae549e93e 100644
--- a/app/models/pull_request.rb
+++ b/app/models/pull_request.rb
@@ -125,7 +125,7 @@ class PullRequest < ActiveRecord::Base
   def self.check_ref(record, attr, value)
     project = attr == :from_ref ? record.from_project : record.to_project
     return if project.blank?
-    if record.to_project.repo.commits.count > 0
+    if record.to_project.repo.branches.count > 0
       record.errors.add attr, I18n.t('projects.pull_requests.wrong_ref') unless project.repo.branches_and_tags.map(&:name).include?(value)
     else
       record.errors.add attr, I18n.t('projects.pull_requests.empty_repo')
@@ -179,8 +179,8 @@ class PullRequest < ActiveRecord::Base
       system 'git', 'tag', '-d', from_ref, to_ref
       system 'git fetch --tags'
       tags, head = repo.tags.map(&:name), to_project == from_project ? 'origin' : 'head'
+      system 'git', 'checkout', to_ref
       unless tags.include? to_ref
-        system 'git', 'checkout', to_ref
         system 'git', 'reset', '--hard', "origin/#{to_ref}"
       end
       unless tags.include? from_ref
diff --git a/app/views/projects/base/_submenu.html.haml b/app/views/projects/base/_submenu.html.haml
index 67b6fb37d..e74348da6 100644
--- a/app/views/projects/base/_submenu.html.haml
+++ b/app/views/projects/base/_submenu.html.haml
@@ -1,5 +1,5 @@
 - content_for :submenu do
-  - act = action_name.to_sym; contr = controller_name.to_sym; treeish = params[:treeish].presence || @project.default_branch
+  - act = action_name.to_sym; contr = controller_name.to_sym; treeish = @project.default_head(params[:treeish])
   .left
     .table-sort-left=image_tag visibility_icon(@project.visibility)
     .table-sort-right=@project.name