I've always heard/read that a *stripped* AR15 bolt should be able to spin freely inside the carrier when the cam pin is removed. Is this not true? Every bolt and carrier I've ever used has done this.
However, I've now encountered two new LMT bolts that severely bind inside their new LMT carriers when trying to rotate them. Bushmaster and Colt bolts spin freely inside these LMT carriers; the LMT bolt rubs, but not binds, inside the Colt and Bushmaster carriers.
Is there anything wrong with these LMT bolts, or are they just super-tight and need to be broken in?
Also, the LMT bolt face has a very light ring machined into it in the exact location of the "fired primer dirt ring" left after firing. What's the purpose of this ring, and why have I never seen it on a bolt before? Thanks in advance.