12/14 gauge greener

I have a 12/14 gauge greener police shot shell made in 1952. I has a partial star crimp and a shot wad with SG on it. What was the shot size in these?
Thanks for any info. frogbert.

Ref: The Gun, and it’s development" by W.W.Greener
Walker, Parker & Company of London show SG as having 11 pellets per Ounce
Abbey Improved Chilled shot company in Newcastle shows SG at 8 pellets per Ounce
Montreal Rolling Mill (Canada) shows their SG at 11 pellets per Ounce and that it has a diameter of 30-100 (.300"?)

I want to note that he shows some 10 “Americian” shot makers, and each has a different pellet count for the same size, and often there own “private” designation for the various sizes.

Today’s standardized “Number 1” buckshot is also .300 in diameter, and with 173-180 (depending on alloy) pellets per pound would be real close to what most makers “SG” than was/is

SG stands for Small Goose. small means the size of the shot not the size of the goose. As opposed to LG which is Large Goose. But its archaic. The only application where the use of shot this large would be practical against a goose is from a punt gun where they would be firing into a flock on the water.
With any shoulder fired gun the small number of pellets would give too erratic a pattern to be consistant at goose ranges in the air. The only use for SG and LG these many years has been in military/police applications. I am suprised they were still making cartridges for Greeners as late as the 1950s It must be an interesting cartridge from that aspect alone. (last batch?)

I have it as .32", SSG is .30", LG is .36" But there were no industry standards governing this