These are British .303 Dummy Drill Mark III and as you can see from the headstamps, are of WWI vintage.
These were originally introduced in 1903 with natural coloured boxwood bullets and tinned cases with no holes. In 1905 it was ordered that four holes be drilled in the case for better identification and that new production would no longer be tinned. In 1907 it was ordered that the bullets should be dyed red.
When the Ball Mark VII with a pointed bullet was introduced in 1910 a new dummy drill round with a pointed wood bullet was introduced as the Mark IV, but it was found to be too fragile so production reverted to the round nosed Mark III. Later in the war the all metal Mark V and VI drill rounds were introduced.
Originally the headstamps were cancelled but often during WWI this was omitted.
Picture shows Drill Mark IV, V and two experimental Mark VI.
Regards
TonyE