But why did they have to use SCC 15 in the first place? Olive Drab already existed in British paint schemes.

The point I was making (maybe you missed it) is that the British had the same colors that the US had so why not use them?

So, how many different ways do I have to explain this?? The British already had (and were using) the same ingredients (ochre, and black) that the US were using (Olive Drab) on military vehicles. Most accounts state that the Brits couldn't (??) produce olive drab so they made SCC15 from a different formulation as a substitute for US OD. Why?

How often do you paint an Aircraft Carrier Deck? My guess on this is that it was a pre war colour in limited qty and couldn't be produced later into the war when the need for a british OD was required.

This has been discussed several times before - the the use of SCC 15 as a substitute for US Olive Drab. But why did they have to use SCC 15 in the first place? Olive Drab already existed in British paint schemes. While doing research for painting the carrier Ark Royal I found the flight deck was painted "Bronze Gray" (not to be confused with "Bronze Green!). I made inquiries. A response from Sovereign Hobbies (Colourcoats) revealed that the formula for Bronze Gray was:
White Oxide - 28 lbs
Black Paint - 14 lbs
Ochre - 56 lbs
Plus various thinners and oils.
The result was a light Olive Drab - just slightly lighter and grayer than the US equivalent. This color was used on carrier flight decks. This was a paint color and had nothing to do with Semtex deck coatings.
So...since black and ochre was already available to the British, and was the same formula as US OD (minus the white), why didn't they (the British) just use this instead of inventing the new color SCC 15?

I imagine the simple reason the British used SCC15 in the first place instead of copying US Olive Drab was because it was what they could feasibly manufacture with the supplies they had on hand. They couldn't just get everything they needed from the USA.

Are you serious?? Did something get lost in translation? I said Bronze Gray was similar to OD because it contained two of the same ingredients - yellow ochre and black! If you omit the white from the Bronze Gray formula (yellow ochre/black/white) you're left with OD - the same OD used by US Army since 1917 and made from the same ingredients.