Not to piddle in anyone's Cheerios, but there have been issues with feeding and extracting 9mm in 52s, barrels not withstanding. There used to be an FAQ on the JFPO site about how to mod the extractor to mitigate this. Seemingly, it may not be as simple a drop-in mod as first glance might imply. Anyone considering this may want to see what they can find out before jumping into this.
FWIW
YMMV