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Frankford Arsenal Ring Retaining Fuse for Hotchkiss Shells


BOCN Contributor
Hi all.

I recently came across the "Ring Retaining Fuse" used in my favorite shells, the Hotchkiss 1.65". I found a line drawing (first figure) and, frankly, I could not begin to understand how the damn thing worked.

Well, I finally got a sucker apart and can now share this technology with you.

The second picture shows a disassembled fuse. From right to left the pieces are:
1) Fulminate cup
2) safety disk
3) Retaining collar
4) Fireing pin tube gizmo
5) Firing pin
6) The infamous "Ring"

The way it works is this:

In the "Safe" mode, the ring is slipped over the fireing pin and rests on a shoulder. See the third picture. When the ring is in the safe position it abuts a ridge in the Firing pin tube gizmo which prevents it from contacting the Fulminate cup. Now (here is the cool part) the ring could be forced back to the .. errr unsafe position only when the projectile is accelerated upon fireing. When the ring is forced to the rear position it allows for ~1/4" of travel: just enough to contact the fulminate (last picture).



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A Perfect match on the my fuze parts;

My My doesn't the safety sleeve and needle look familiar. Now if I can just get a designation for mine. The "FA" is definitely Frankfort Arsenal and the date is 1895. Thanks a million.
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Jees Bart. That looks familiar. I need to go thru my Hotchkiss patents tomorrow. I saw that one somewhere.
These aren't Hotchkiss types ?

It should be in that fuse manual you found a couple of weeks back that showed all of the F.A. fuses and such, not in the patents --
Yeah. It looks a bit like plate 4, 3/4 with a couple of differences. That one is dated 1900 so it might simply be the later model.
Frankfort Arsenal Fuze System;

Thanks a million for helping me at least I.Dl the fuze system, perhaps its designation will come later.
Best Regards,
John aka bart
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Frankfort Arsenal Fuze System;

To Birdseye and all Interested:
Hopefully this half sectioned view will aid in understanding how this neat "ring resistance" pin masking sleeve and firing pin function together to arm the firing pin assembly to stab the primer composition.
Best Regards,
John aka Bart
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Frankfort "N" Percussion Fuze;

To Birdseye,
The bdlow fuze is the one I was tyring to I.D. The original is in the P:icatenny (sp)Arsenal Museum.
John aka Bart
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The line drawing and the fuze pictured are not the same. It is a Frankford Arsenal Ring Risitance fuze. The designation is "Point Percussion Fuze for 1.65 Inch Shell of Hotchkiss Manufacture" Ordnance Pamphlet No.1727, Fuzes for use in Mountain, Siege, and Seacoast Projectiles and in Detonating Fuzes, Washington: GPO, 1908


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