Mills grenade bursting charges

[Bannerman]

A variety of different bursting charges were used in Mills grenades. Is it possible to say what physical form these charges took? Were they powder? Flakes? Crystal? Or a molten pour-in/set on cooling compound?

Once filled, did the grenades have a defined shelf life and if so, do we know how long? Could a filling be removed and replaced?

In TGRM vol 2, with regard to the No 36M Mk1 (L) it states "All grenades with a filling of Cilferite C were withdrawn from service and destroyed in December 1932". Why was this?

Bruno

 

[Bannerman]

Hullo again,

More fiddly and detailed questions, anyone got any ideas?

Regards
Bannerman

 

[Nismosonic]

im not sure, Ive been told a few times that Amatol filling was in powder form, I doubt it was a solid as there are so many empty Mills Bombs around, and to inert these would be more trouble than its worth if its a set solid.
whereas a powder can be simply shook from the grenade once the filler plug is removed.
i too look forward to the answers on the thread you posted. :tinysmile_twink_t:

 

[ammocat]

Bursting Charges

I have some reference material at work, so when I get back on Tuesday I will see if I can find some better information.

The No. 36 Mk 1(L) was filled with Ammonal, Alumatol, Amatol, or Cilferite.

Amatol is made by mixing TNT with ammonium nitrate, this can be done two ways. Heating the TNT until liquid and mixing in the ammonium nitrate and the resulting explosive can be poured into ordnance. It can also be made by mixing TNT flakes with powdered ammonium nitrate which could be pressed into ordnance. This is a lower grade of amatol.

Ammonal is TNT, ammonium nitrate and aluminum powder. The aluminum makes it more sensitive to detonation.

Alumatol is also a mixture of TNT, ammonium nitrate and aluminum powder.

Ammonal, Alumatol, and Cilferite are all listed as hydroscopic, so I am assuming that over time these explosives would absorb moisture from the atmosphere which would reduce the effectiveness of the explosive, possibly leading to an excessive duds.

The No. 36M Mk 1(L) was filled with Trotyl, Baratol, and Cilferite.

Trotyl is TNT. TNT is expensive and complexed to manufacture. TNT is also prone to exudation in warm environments which can lead to increased shock sensitivity and accidental detonations.

Baratol is TNT mixed with barium nitrate.

By mixing TNT with other materials such as ammonimum nitrate or baruim nitrate you can stretch how far your TNT will go, reducing the required production of TNT. The produced explosives may also have more desireable storage characteristics. Sometimes these mixtures can increase the effectiveness of the explosive. As an example TNT has an Reactive Effectiveness (RE) factor of 1, whereas Amatol has an RE factor of 1.17.

 

[SG500]

im not sure, Ive been told a few times that Amatol filling was in powder form, I doubt it was a solid as there are so many empty Mills Bombs around, and to inert these would be more trouble than its worth if its a set solid.
whereas a powder can be simply shook from the grenade once the filler plug is removed.
i too look forward to the answers on the thread you posted. :tinysmile_twink_t:

Just a thought........a lot of the Mills grenades out there are drill ones that have been...........upgraded by having the holes filled in so wouldn't have had any explosive in them in the first place. Yes there are loads that would have had HE filling in them but not as many as you may think.
Dave.

 

[ammocat]

Bursting Charges

I have done some reading today and I believe that most of the bursting charges in the No. 36 grenade must been cast explosives. Amatol, Ammonal, and Baratol are all listed as being cast explosives. Trotyl (TNT) is listed as being cast or pressed, although I don't see how you could press TNT into a grenade body.

I have not been able to find any information on Cilferite. More research to come.

 

[Bannerman]

Thanks for your input guys, very helpful
Cheers
Bruno