That bursting bomb insignia was not the exclusive property of the Marine Corps (e.g., Marine Gunner, Gunnery Sergeant). See chart below (Ordnance Sgt, USA)
Prior to WW II The Marine Gunnery Sergeant rank looked like this (below), both bursting bomb & crossed rifles...
And, prior to that (from 1906) again, both crossed rifles and bursting bomb, but no rockers/straight bars!
The first Gny Sgts came in 1898, and their insignia consisted of three chevrons, three straight bars, w/a bursting bomb, MC Emblem, and crossed rifle and naval piece!
Later, WW II, the GnySgt insigne looked like this....
Still later, 1946, the GnySgt rank became extinct, replaced by the Technical Sergeant
(T/Sgt prior tp 1946 w/3 chevrons, two straight bars)
T/Sgt, TechSgt, after Dec 1946 then w/same previous chevrons/insigne as for previous GnySgt.
But then the T/Sgt was unofficially refered to as "Gunny," and wore the same previous GnySgt insignia/chevrons. (Ironically, the Technical Sergeant rank had long previously specifically been created for Gunnery Sergeants not actually serving in GnySgt duties.)
So, when the GnySgt rank was exhumed w/the rank structure change (1958-1959) why was the GySgt not given back his bursting bomb?
Well, no specific explanation for that is provided, but for one thing, the new rank structure then/now had two new ranks created at the top--"super-sergeants"--and the traditional bursting bomb of the Marine Gunnery Sergeant went that-a-way. Don't blame the Marine Corps--the new rank structure together w/its silly super-sergeant ranks was the work of the DOD.
R.W. "Dick" Gaines
GnySgt USMC (Ret.)
1952 (Plt #437)--'72
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