Red paint was commonly applied to .30-06 cal US Army rifles in Brit/Commonwealth service to distinguish the need for .30-06 rather than standard .303 Brit ammo. You can find this on all of M1917, M1903 and M1 Garand rifles used by the Brits in WW2. Sometimes the red band on the forend was also marked with .30-06 or Cal .30. Look for a C/broad arrow stamp on your rifle. This would indicate Cdn issue/use in WW2. M1917s were used by all of POW Camp guards, RCAF ground defence personnel, and various reserve units in Canada in WW2.