The Chemistry of Powder and Explosives - Sciencemadness Dot Org

414 PRIMARY EXPLOSIVES, DETONATORS, AND PRIMERS
be, manufactured. The original fulminate detonators were numbered
according to the amount of fulminate which they contained,
/Reenforcing
/ cap
^Initiating
explosive
- High explosive
Wires
Sulfur plug
Tar plug (waterproof)
,Wire bridge
Match head
sealed In fiber tube
Initiating explosive
High explosive
FIGURE 95. Blasting Caps. Detonator crimped to miner's fuse. Compound
detonator. Compound electric detonator.
the same numbers being used throughout the world. The charges
of fulminate for the various sizes are shown in the following table,
Detonator
No. 1
No. 2
No. 3
No. 4
No. 5
No. 6
No. 7
No. 8
Weight of Mercury
Grams
0.30
0.40
0.54
0.65
0.80
1.00
1.50
2.00
Fulminate
Grains
4.6
6.2
8.3
10.0
12.3
15.4
23.1
30.9
External Dimensions of Capsule
Diameter, mm.
5.5
5.5
5.5
6
6
6
6
6-7
Length, mm.
16
22
26
28
30-32
35
40-45
50-55
along with the usual (but not universal) dimensions of the cylindri-
cal copper capsules. The same numbers are now applied to com-
mercial blasting caps of the same sizes, whatever the weights and