checkout to a reflog entry

Sometimes when git reflog and try to checkout to a previous commit, 

project((6a33dbc...))$ git reflog show master 77aa688 master@{0}: rebase -i (finish): refs/heads/master onto fc3eaa4 6a33dbc master@{1}: commit: wip .....

project(master)$ git checkout master@{1}
Note: moving to 'master@{1}' which isn't a local branch
If you want to create a new branch from this checkout, you may do so
(now or later) by using -b with the checkout command again. Example:
  git checkout -b <new_branch_name>
HEAD is now at 6a33dbc... wip
project((6a33dbc...))$ 

project((6a33dbc...))$ git branch
* (no branch)
  master

It becomes (no branch) although the SHA1 is correct. If I then checkout master, then it revert and jump back up the previous master HEAD. I tried HEAD@{xx} also failed. What is the correct way of to checkout that master@{..} and stay in that master branch? (Sometimes it worked I forgot how and why)

On Tue, Aug 25, 2009 at 12:52:35PM +0800, bill lam wrote:

A reflog entry is not a branch; it is just a pointer to the commit where a branch was at some point. Using "git checkout" on it will let you explore the contents, just as you might with a tag. If you want to build on it, you need to either:

  1. Make a new branch to work on, starting at that point:

       git checkout -b my-topic master@{1}

  2. Reset your current branch (and worktree) to point at that commit:

       git reset --hard master@{1}

-Peff

On Tue, 25 Aug 2009, Jeff King wrote:

Thank you for explanation on the difference between checkout and reset.