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Hi this is first time I've been on your forum. I find this thread really interesting. My deceased Grandad was injured at dunkirk and subsequently went on to be one of 25 men who manned one of 3 new "big guns" at dover castle ordered by Churchill. I have been searching for 3 years on ancestry and findmypast, etc but have not been able to find his service record or number. I would love to apply to m.o.d for his service record but don't know his service no. I am actually at Dover at the moment to take some photos of where he served. Any hints or tips on how i can find more info would be most welcome. I contacted the Royal Artillery museum but they said he could have been in the army or navy depending on his unit so don't want to waste £30 asking for details from the wrong service. Many thanks for any help you can give me.