Convering Military times to standard time

Transact-SQL
1

I have a time column that holds times like this 00125, 01230, 02310
My question is how would I change these into something like 12:30, 1:25, 23:10?
Is it as simple as doing a concat and left() statement and then convering that to datetime? Or is there a better way?

2

STUFF(RIGHT('0000' + CAST(time AS varchar(4)), 4), 3, 0, ':')

3

I came up with this

CONVERT(VARCHAR,(LEFT(A.START_TIME, 3) + ':' + RIGHT(A.START_TIME,2)), 8)

but this gives me numbers like 011:28 and does not let me then convert or cast to something useful like time.

4 
DECLARE @t table( tm varchar(5) );
INSERT @t ( tm )
VALUES ( '00125' ),( '01230'),( '02310' );
SELECT 
   Stuff( Right( tm, 4 )
        , 3 -- before the third character
        , 0 -- replace 0 characters
        , ':' -- stuff this string
        ) TimeStuff
 , Substring( tm, 2, 2) + ':' + Substring( tm, 5, 2) TimeSubstrings
FROM @t;

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