No.4 rifle serial number query

[krinko]

MC24730 is a 1944-45 Fazakerley made No4 Mk1.
At the time, FAZ was using three series of letter prefixes concurrently---marked A,B,C.
They had a trick to them. They ran like this: AA, BA, CA---AB, BB, CB---and AC, BC, CC etc.

So, "MC24730" breaks down like this: "M" is the 13th series of 9999 rifles in production line "C".
The first "2" is the factory number for FAZ and doesn't move, so when the counter gets to "MC 29999", the prefix switches to "NC" and so on. Muddy enough for you? Sorry for the quick and dirty answer, but I am needed elsewhere.

(Maltby numbers start with a "1", so no possibility this is a Maltby mistake.)

-----krinko