Stored Proc Taking Too Long

Dear All

I have a stored proc that is taking way too long to process, over 50 minutes.

What I need to do is go through 180K rows, and if the projId and langid is the same, increment 1 to a value, if not, reset the incrementer

I am doing the following at the moment

DECLARE @Id int, @ProjectId int, @LangCode char(6)
DECLARE @CurProjectId int, @CurLangCode char(6)
DECLARE @incrementer int
DECLARE Order_cursor CURSOR FOR

SELECT Id, langCode, projectid FROM #tempTable

OPEN Order_cursor
SET @incrementer = 1
FETCH NEXT FROM Order_cursor INTO @Id, @LangCode, @ProjectId
WHILE @@FETCH_STATUS = 0
BEGIN
IF(@CurProjectId = @ProjectId)
AND (@CurLangCode = @LangCode)
BEGIN
SET @incrementer = @incrementer + 1
END
ELSE
BEGIN
SET @incrementer = 1
END
UPDATE #tempTable
SET edbOrder = @incrementer
WHERE Id = @id
SET @CurProjectId = @ProjectId
SET @CurLangCode = @LangCode
FETCH NEXT FROM Order_cursor INTO @Id, @LangCode, @ProjectId
END
CLOSE Order_cursor
DEALLOCATE Order_cursor


Is there a better way?

Thanks

Johann