The original QF 6 pounder naval gun had turned out to be too long for use with the current British heavy tank designs, which mounted guns in sponsons rather than turrets, the muzzles of the long barrels sometimes digging into the mud when the vehicle crossed trenches.
When the vehicle crossed trenches. This was what the original QF 6 pounder naval gun had turned out to be too long for use with the current British heavy tank designs sometimes digging into the mud. The current British heavy tank designs mounted guns in sponsons rather than turrets. Sponsons rather than turrets were the muzzles of the long barrels.