According to Midway, " Factory 1911 recoil springs are 16 pounds in 45 ACP, 14 pounds in 38 Super, 9mm Luger, 38 Special Midrange, Colt Ace 22 conversion kit, and 19 pounds in 40 S&W.
# The Delta Elite 10mm uses a dual factory spring rated at 23 pounds. Single recoil springs require that the Delta Elite recoil spring guide be replaced with a standard 45 ACP recoil spring guide."
No idea re: length in the officer's, but the government models and Commander models should use the same length spring as the 45.