Same ref. as Mr. Nixon on page 51 there's a pic of a 1907 price list where a No.2 Krupp is offered, so there were steel tubes. Also on page 352 Mr. Snyder gives the "chamber bores" and before August 1924, the Ithaca 12 gauge was 2 5/8" and after 2 3/4" and the same for the 16 gauge. The change for the 20 bore occured in October 1926.

Kind Regards,

Raimey
rse