I don't know why I bother checking on this thread.
When it all fails miserably, he'll just come on here and say how great it worked; provided he doesn't seriously maim or injure himself in the process.
A 5.2 Mag block? He'd have better results by not boring it at all with that contraption and just running stock bore pistons- the tolerances would still be tighter. Oh, well- another block on the scrap pile.