Today I've (finally) found THE info that I've casually researched for many years, of my father's details as a Gunner in 90 Field Regiment Royal Artillery 357 Battery (I've previously looked-in vain for 92nd field and failed ~ explains Why ! )He was in main, the driver of the Batt OP tank – now found to be 'Aurora' ~ pretty-good definitive for One individual among the millions serving!!
The question I'm responding to, is about the 'Imitation gun' mounted and I can from 'memory' relate His stories (few) about….
There was a 'tin' barrel on his tank, which used to 'flex' because the metal gauge was so thin. There was no breach obviously. The Reason for it being unarmed was, the space in the turret at a premium, was occupied by multi-net radio-sets ~ to talk to multiple batteries and commanders etc. all netted separately. He of course carried the OC / FOO. The limitation on available space also precluded a co-ax but, he was fitted with a roof mounted Bren-gun (sometimes) ~ would you credit, Twice it was Stolen off the laagered tank !
He was 25lb Gypsies in North Africa (Indian Division Artillery) (2nd Battle of Alamaign etc) and were returned UK to re-equip for what turned out to be Normandy. He landed Sword Beach at D -20m … LCT designed to carry 4 ~ they (you're probably aware) found that by leaving the inner doors open, that a fifth tank could be crammed-in…. His was #5 solo in the bows. D-30 they sailed-in 'shelling' (not him) the coastal defenses and then did a U-turn short and were sailed through by the assaulting Infantry landing-craft, then U-turned again to land in close support. At this point, there was supposed to be a 'start-engines' signal – His tank was powered by x4 omnibus engines, which had to be individually started and then syncromeshed so, it took 20 minutes to achieve.
He was sat 'head-up in his tank when the ramp crashed down and green tracer came in ~ signal neglected, they'd arrived at Normandy ! He then (head rapidly down) had to start/engage his 4 engines sat in the mouth of the LCT under small-arms fire for the Most rapid start-up he'd ever achieved !! – with of course, the gunned Sextons of his troop blocked-in behind him.
Some other stories but not many as, with vets aplenty (now its PTSD) he was affected by, yet survived the war, though the 'smell' of wet broken bricks caused him 'instant' vomiting (flashbacks), including having been in the action against Wittman at 'damn name escapes me ~ Tilley-sur-seul ?' where (story) the battery shelled a French village over 'opensights' ~ sheltering Panzers ~ while the villagers stood alongside his tank 'Cheering' every explosion that was knocking their houses Down ! (He didn't get-it'! ).
Hope this has been of some interest.