It's about a 2A1 being a 7.62 and not .303 Brit. Easiest 'tell' is the square mag though.
No paint on CF rifles. Painting 'em with lines was primarily a W.W. II Brit thing with all the assorted Lend/Lease kit laying around. India did it's own thing. Never seen any Aussie kit with paint indicating a rifle was safe to use either.
Drill Purpose stuff was stamped 'DP' by the Brits. We just left the breech block out of our weapons. No. 4 rifles were just not loaded for parades.
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