unknown firing pin.

[RNLMC]

hi gentleman.

I recently found this item at a jumble. I think it is a firing pin of some sort.
can anybody identify this here item.
length= 3.178 inch
bottom= 1.744 inch
top= 0.198 inch.
The bottom reeds top at 1 end, and a M in a circle followd by a number: D69286, and a H underneath.

any thought`s on this are most welcom.

regards. werner.

 

[tankbarrell]

It's an M15 firing lock from a 75mm gun M6 fitted in the M24 Chaffee light tank.

 

[RNLMC]

thanks tankbarrell. now i have to find a M24 to see the whole picture.
My first thought was mortar or cannon, never thought of tanks.