Here is my SWAG... The problem is the steel/polymer case of the Wolf doesn't expand to seal the chamber the same way a brass case does. As a result, you are getting carbon buildup on the chamber walls. Since the Wolf doesn't expand as much and is operating at lower pressures, it runs fine.
However, once you throw in the brass cased ammo, you have two problems - 5.56mm pressures (instead of .223) and a brass case that expands more than steel. When you fire this round, it tries to expand more in the now slightly smaller (due to carbon buildup) chamber. Due to the higher pressure and the smaller space, the brass sticks longer than it normally would and your bolt is using up all of its energy just trying to pull the stuck case out of the chamber - as a result it fails to extract fully or eject.
This is probably being helped along by a bolt and bolt carrier group that is marginal on lubrication.
If I did guess the problem correctly, then there are a couple of solutions:
1) Clean the chamber very, very thoroughly with a good cleaner like Carbon Cutter or somethinhg especially designed for baked on, tough carbon deposits like those found on the tail of the bolt. Also use a chamber brush and a fixed (non turning) cleaning rod.
2) Always fire Wolf ammo last when using a mix of brass cased 5.56 ammo and Wolf.
3) Make sure your AR15 is properly lubed. You can often make an AR15 that won't function work by just adding lube until the bolt and bolt carrier are drenched in it. I'm not saying it is the optimum solution and it will attract dust and other gunk eventually; but if you need a quick fix to keep it running, that will work a lot of times (and for quite a few different problems even).
i forgot to mention: i tried my bushy's B/BCG and this upper worked fine, so its not the buffer area, but more than likely the original B/BCG (extractor/spring ) that is the problem
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Have you compared the headspace on the rifle with each bolt? Could be that one bolt has a different enough headspace to allow pressures to stay lower and so the gun continues to function. It could also be that I am completely hosed on this line of thinking and there is another problem entirely; but testing my theory should be pretty simple... just clean the chamber and try the brass 5.56 ammo first and see if the problems continue.
But I am betting money you have a pressure problem in the chamber area... the fact that it works with underpowered Wolf ammo; but doesn't work with 5.56mm pressure ammo screams it out. Plus the symptoms you are describing are exactly what happens when you have too much pressure in the chamber of an AR15.