Yesterday I fired off 150 rounds or so, and after about 75 rounds a Wolf round (this isn't an anti-Wolf post - read on) got jammed between the bolt and the charger.  It was jammed bad.  I finally had to dent up my brother's pocketknife to get it out.  I had to try to pull the bolt carrier back and keep the charger from moving.  When it was fixed I went on shooting.  A little while later, I got another jam.  This one was a Q3131A round.  Both times it was the last round in the magazine that got jammed.

Is it a problem with the magazine?  I don't know what kind they are - they have no name on them.  All I can tell you about them is that I got them from Cheaper Than Dirt.

I've had the same problem with the last round in the nine-round Colt mag that came with my AR. Check if there's a lip on the front edge of the mag. The last round can get pushed forward and snag on the lip. Filing or cutting off the lip may solve your problem. A stronger spring might also work. I haven't tried either solution. I just don't use that mag.

Sounds like a USA mag to me, is this one of those $10 black aluminum mags that CTD sells.

It sounds like the problem is that the mag has weak feed lips and the last round is jumping out of the mag when the bolt carrier is all the way back allowing the bullet to get jammed up in the workings. Try loading one round into the mag and give it a good whack against your hand and see if the bullet will jump out of the mag that way. I would suggest you pick up some decent mags for your rifle.