The 3 inch 20cwt renown as a AA round during WW1 and into the Second world war but it seems it also was used by the Navy in the form of solid practice shot and was also used in the Churchill tank. I also read somewhere that AA positions where given AP rounds during WW2 if the Invasion turned for the worse and we had to point our AA guns at ground level as anti tank guns, in the book AA Command. I have two solid shot projectiles with missing copper bands and are marked, I/N QF 3in 20cwt 16lb P CI RL 6/45 Lot 18. I noticed that there is an original red painted band on nose of both projectiles, one slightly higher than the other which you can just about see but is clearly there. I thought that if it were Naval practice shot the markings, especially on the 2 pounder were marked with a yellow band with a large white capital N stencilled on the side. So why the red band on the 3inch, is it Naval practice but they marked them differently or are they not but used for something else. How would these be marked up, black body with red band and a white letter N?
Still used by the RN as an AA gun throughout WW2 with HE ammo. Details here might help:- Britain 12-pdr [3"/45 (76.2 cm)] 20cwt QF HA Marks I, II, III and IV - NavWeaps
So classed as a 12 pounder, interesting. I have been finding out about solid shot practice rounds but cant seem to find anything, wondering if all calibre's were marked up in a similar fashion like black body red or yellow banding etc.
Upon closer examination of the remaining painted red band after lightly scraping the paint, it turns out that it is yellow. I assume that all Naval practice shot was stamped up with a large stencilled N to denote Naval use.
I wish I could be more help, but you might want to post on this Inert Ordnance Collectors forum. Inert Ordnance Collectors As far as I know the only use in the Churchill tank was in the Churchill Gun Carrier which replaced the turret with a box superstructure and mounted the gun to the front with limited traverse. The guns were (I think) surplus navy weapons. At the time they were conceived I don't think the 6-pounder gun was in production.
