2 WWI British 6 Pound Artillery Casing Marking Identification

I have 2 British 6 pound casings. I was wondering what all of the symbols meant. More importantly the Anchor and the "B, Crow Foot, number" on each. Below is what I have been able to find out with some research:

6 PR: 6 pounder artillery shell
Roman numeral III: Mark III (3) casing (What is a Mark III casing?)
Lot 182: Lot number case was made in
Letter “K”: Manufactured by Kynoch Works in Witton, Birmingham, England
1917: Date made
Anchor symbol: Used on Naval ship??
CF: “C” stands for cordite and the number of “F's” depict how many times it was filled full (Cordite Full Charge filled once)
B, Down Arrow, 93: filling station and loading lot??? Inspector's stamp??? If so, where/name?
1 with a circle around it: fitted with a Mark II Primer
Crows foot (arrow): British property marking and accepted for service (Is this the arrow between the “B” and “93?”

Anything additional or any affirmation would be greatly appreciated. Thanks!