British britten Percussion Fuze;

[John D. Bartleson Jr.]

To All Interested,
      Not a Blakely, not a Preston, but the fuze invented and patented by Sir Bashley Britten along with his lead saboted projectiles that was manufactured by Preston-Fawcett in the UK.
As shown below, the Britten is a simple percussion fuze consisting of a fuze body, striker and lead striker safety disk and the cap or anvil.
      Lead is poured in from the base to grip the striker around its encirciling groove.  At impact the striker breaks away from the restraining lead and strikes its 'top hat' percussion cap against the inside of the cap.  The fuze body and cap threads are 14 tpi and are left hand.
     Some strikers are seen with several grooves and the fuze bosy on some models is minus the wrench flats. Enjoy.
Best Regards,
John

[joevann]

So, with the striker being tapered to the rear, it is held in place by onlt the thin amount that enters the groove during casting.  This seperates at impact allowing the striker to impact the cap.  Very elegant engineering and manufacturing solution.  I assume the purest lead was used.  Are there any test data showing the force required to release?

[John D. Bartleson Jr.]

Joe,
No data that I know of, however with a punch the striker popped right out of the fuze body.
It is rumored that the striker would sometimes cant sideways in the fuze body and be a dud, again, no evidence that I know of.
If anyone has comments please come forward.
Regards,
John

[Dave the plumber]

          John,      I have seen alot of dud Britten shells with obvious rifling definately fired.  With that said, the dud percentage for all the types of fuzed shells is very, very high.    It must have been depressing for the gunners...

[pipedreamer65]

Excellent diagram, it is spot on.  I popped a slider out of a 4" Preston Blakley via a hole drilled in the bottom of the shell.  Inserted an oak dowel in the drill hole, two hard hits with a hammer and it came on out.

[John D. Bartleson Jr.]

Hello Pipedreamer,
    Would you post some photos of your projectile and its fuze?
BTW, evidence is mounting that your shell is really an inventionof Commander Scott, RN.   The flanged projectile was not invented nor patented by Blakely and Preston of Preston-Fawcett was the manufacturer for Scott and for Britten projectiles.
    The two projectiles were provided with the Blakely rifles when shipped to the U.S. and to Peru as it fought with Chili and Spanish vessels off the Peruvian coast.
The shell shown below is an example of the Britten Fuze without the wrench flats.
Thanks for your input.
Best Regards,
John

[CarlS]

Here are some examples of the fuse that were found in a camp near Corinth.  They appear to be unfired as it wasn't a battle area and they are perfect.  The domed covers weren't found so I'm looking for some to add to make them complete.  Note the grooves on the slider to grip the lead as discussed.  Also note the buse body is the early style without the flange.

[John D. Bartleson Jr.]

Carl,
  Can you post a view looking down inside the fuze body? Close up, hi-res and clean.
Joh

[CarlS]

John,

There is nothing to see but a smooth path down the middle with a very small lip on the bottom edge.  I would never be able to get that to show with my photography skills.  In fact I bet some of these have been found and thrown away as a gas or plumbing fitting as there is nothing distincive about the body.

The slider is rather heavy compared to most given it's size.  It is solid brass with a small hole drilled from top to bottom. 

[joevann]

Carl,  is it just a trick of the lighting or do those fuze bodies have a left-hand thread?

Regards,

Joe W. Vann III

[CarlS]

Joe,

You are correct.  I think they are like the one John drew to open this discussion but without the flange.

[John D. Bartleson Jr.]

Joe look in the lower left corner of the drawing.
John

[joevann]

Now, that leads to another question:  Why?  Does the artillery piece they were designed to be used in have left-handed rifling?  If not, this would have a tendancy to make the fuze unscrew in flight.  That is why in modern projectiles with right-hand rifling, nose fuzes have right-hand threads and base fuzes have left-hand threads.   Or, is this more of a problem with base fuzes than nose fuzes?

[CarlS]

John,

Good questions for those who read and study this in great detail but I can say that the Britten shell used this fuse and it has left handed threads.  A very similar one with the hexagonal flange is made for the Blakely (aka Preston) shell.  As far as I know they are all left handed threaded.  Seems to be a British thing.

[pipedreamer65]

Yep, left handed threads.  A great thing to know before you try to disassemble one.  These days, left hand threads are used to prevent something from unscrewing during operation, like a bicycle pedal.  I'm sure there are other uses.  I have no idea why this particular fuze is left handed.  I assumed it was a "british thing" myself, or perhaps a personal choice made by the inventor, before right handedness became standard.  Have no idea about shell rotation...hurts my head to think about it.