British Boxer Diaphragm Shrapnel Shell;

[John D. Bartleson Jr.]

David,
   I really needed to start a new topic with this smoothbore projectile.
Col. Boxer developed this design in order to separate powder from shrapnel to prevent just what your comment suggested.
Hopefully the color plate speaks for itself.
Cheers,
John

[Dave the plumber]

       I never knew such a shell existed. Thank you John.      What is a patent or year produced range ??      And did they actually cast them and use them in service ??
       Interesting that if the shell burst with the powder charge forward in flight, it seems like a lot of the momentum of the case shot going forward towards the target would be lost.     But I'm sure they figured out a way to overcome this..... or it wasn't that critical

[John D. Bartleson Jr.]

David,
   The color plate shown above is from a Royal Laboratory plate dated July 1863.  I do not know the exact date of invention and of course it was in use prior to this date. There are pro and con comments about its effectiveness.  Remember a spherical spins somewhat in flight unlike a rifled shell which, for the most part, remains in one plane with the fuze forward.
Perhaps this was one of its shortcomings.  I am certain our method of construction was more efficient and worked better.
Cheers,
John

[joevann]

Yes, Dave they were used and are mentioned in most American ordnance publications of the period.  John knows whereof he speaks.  In the trajectory of a sphere, the location of the center of mass is irrelevant.  Note the number of different spherical shells with eccentric cavities for the powder charge.

[Dave the plumber]

I know the 9 and 11 inch shells we find here have the culot piece or counterweight opposite the built up iron of the fuze area, I always thought that was for stability in flight.......

[John D. Bartleson Jr.]

David,
   During Hubbell's 1871 claims for regress of others using his alleged use by the U.S. government, the claims court committee adjudged that his shell invention which included a flat side opposite the fuse hole was useless and did not work as claimed.  Accordingly his claim was denied.
Cheers,
John
P.s. Did I answer your question concerning the Diaphragm shell?

 

[Andrews148]

I believe I have found one while metal detecting in Jersey, Channel Islands. I think mine came from a 24 pounder cannon.

I have left it on the beach until it has received EOD attention. Is it something that could be made safe?

[Dave the plumber]

    great find !!     Does EOD preserve relics / disarm in the UK, or do they blow them up like they typically do here in the US ?   It would be a shame to loose this shell.  At least ask for the fragments returned to you. And hopefully the entire shell, or at least the fragments, will have to be run through electrolysis for quite awhile.  But, it is worth the effort !!

[Andrews148]

Our local EOD officer will preserve historical ordnance, where possible. He has emptied explosive cannonballs for other detectorists.
I wouldn't have the space or knowhow to perform electrolysis. My other cannonballs are currently soaking in a caustic soda solution for the foreseeable future!

[CarlS]

A couple of interesting things to note from the picture:
1) The brass side plug looks like someone tried to remove it and the screw driver slipped.
2) There is an "X" or something similar just below the fuse.  That an arsenal mark?