This rifle was not upgraded and is still in it's M1922M1 configuration. It has an "I" instead of a "1" after the M1922M. I am familiar with the fact that most of the M1variants were converted to M2. This one somehow escaped. It has no letter "B" added to its serial number. The father purchased a 1911 from the NRA and this rifle may have been purchased around the same time.
Bill