Shawn:
If a 3.67" was reamed and rifled to 3.8", would it not become a 3.8" James rifle? The James type I rifled field gun were reamed from old 6 pounder field guns, bore diameter 3.67", to a 3.80" rifled gun with 15 grooves with a right hand twist. This bore diameter was selected because it was the size a damaged bronze barrel could be reamed and bored with consistency and safety.

If there were any actual 3.67" rifles, they were unstandard guns, may have a few 6 pounder field pieces that were bored as a test measure or other reasons. None of these were referred to as James Rifles.

Regards
Ron