Originally Posted by T-Mar

Without performing destructive measurement , the only 2030 tube that you''ll get a wall thickness measurement for is the seat tube. Most of the 2030 bicycles used 25.4mm posts, if I recall correctly, so you're looking at about 1.5 mm wall thickness, versus 0.8 - 0.9mm for a CrMo or MnMo, plain gauge seat tube from the likes of Columbus, Reynolds or Tange.

Most other manufactuers used similar steels in their entry level frames, though I believe that only Raleigh used the 2030 designation.