Happy to show the world.
The Engineers on this site will probably be horrified at using a drill but I am not trying to make a steam engine.
I can usually get to within about 0.05 mm. of the right dia. and length.
I have a 13 mm. Makita hammer drill with reverse but no speed control unfortunatly.
Just held in a 4" vice on the bench.
Light cuts only as the drill bearings are not meant for side pressure although the hammer drill bearings are probably better than a plain drill.
For turning I use a series of files from 150 mm. down to needle files and wet and dry paper.
I also use a jewellers saw or junior hacksaw to cut narrow slots and 'square' corners.
The files need to be cleaned with a fine wire brush to get rid of the swarf that clings to them.
Most of the material I turn is brass rod but I have used aluminium and a little steel.
The reverse is really useful as files cut differently in each direction.
Only have the minimum work sticking out of the chuck and try to finish that part before moving the rod out for the next cuts. (As per Glens gun barrel shown below)