British 0,303" drill round drawing

A drawing showing a sectioned view through an 0,303" drill round. Nothing too surprising but I was taken with the outward flaring of the bottom edges of the empty jacket to provide extra security.


Is there any other information on this, or A.C. Hales Patent No. 16769/42.

Seems to be very close to the Drill Mark 9, which is of the same era.

Peter, as usual, thank you very much for posting all these drawings.

John, below you can see the patent’s drawing:



Thanks Fede, great stuff.
Do you know if the patent number indicates the patent was dated 1942.? It was also interesting that he covered three different types, jacketed one piece wood filler, same in two piece filler, and what looks like an unjacketed type.


John, that is the application date (November 26, 1942), while the complete patent specification was accepted on June 1, 1944. Regarding the drawing, fig. 1 and 2 shows the same construction (unformed and formed); fig. 3 is a variation adding a mouth crimp; fig. 4 and 5 shows another construction without bullet jacket (unformed and formed); fig. 6 shows yet another construction having a metal core with a projection that fits the wood spacer. Regards, Fede.

Thanks a lot Fede.