Don't want to hijack this thread but curiosity has got me. I've seen a few posts of folks going to the Zipper and am wondering why they didn't select one of the 22/30-30 improved cartridges. Ackley, ICL and a few others made versions that outstep the Zipper and are within 100 FPS of the 22-250. The downside I see is having to form the brass as modern Zipper brass will not form without splitting nearly every case even when using cornmeal and a Unique or Bullseye forming charge.
Mike