That is a bummer. I got the LC about 3 weeks ago, and it has a LOT of rough spots that need working thru. I am not really thrilled with it, but I am trying real hard to like it. (I am trying exactly $475 out the door to like it....
)So far, the trigger is the worst of it. It feels rough, trigger is getting better after nearly 250 rounds and 3 massive oilings/ cleanings.
My thoughts on your extraction issue: 1st, get a bore brush that you don't mind wearing out. Lug it into a drill and with oil, polish the chamber a bit at relatively low speed. If the chamber is a bit rough, this will clean it up in there quickly. (I have done this on MANY of my guns, especially my duck guns, which get flooded in marshy semi salt water.) Next is to really oil and work over the extractor. Liberally dose that thing and work it to death. Simulate 200 rounds of extraction and keep adding a drop of oil or 2 every dozen workings.
Lastly, after reassembly; use a heavier round. Try some 124gr. ammo to see if it makes a difference. I have used 115, 124, 147 with no extractor issues.
Hope this helps.