Case Extraction Woes

My STI Spartan doesn't like MFS ammunition.  I generally buy American Eagle or Sellier and Bellot but the last time I went to the gun store all they had was this MFS steel cased Euro-trash crap.  I'd purchased a box of fifty previously and had no problems so I felt reasonably comfortable buying a brick of a thousand rounds when my local drug pusher gun store was out of my usual ammunition.  I found that about one box in three gave me a failure to extract every three or four rounds.

I finally discovered that the problem was dirt.  The MFS ammunition is a bit dirty and if I take the time to laboriously polish each round then I don't have any extraction issues at all.  You can imagine just how happy this makes me.  My local gun shop seems to have issues maintaining a steady supply of 9mm ammo anyway so I guess it's time to start reloading.