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Shell Building Tables and Other Useful Information.


 
Case Former Dimensions for Cylindrical  Shells.

 
Shell size (inch)
 
  Outside Diameter Inches
 
Former Length Inches

Hole for fuse flash bag

Diameter x depth


 
Insert Formers
 
3/4 - 2
 
6
 
1/2 x 2

 
3
 
2 1/2
 
6 to 7
 
1 x 2 1/4

 
4
 
3 1/2
 
8 to 9
 
1 1/2 x 3 1/4
 
5
 4 1/2
 9 to 11

2 1/4 x 3 3/4


 
6
 
5 1/2
 
12 to 14
 
2 1/2 x 4 1/2

 
7
 
6 1/2
 
12 to 14
 
2 1/2 x 4 1/2

 
8
 
7 1/4
 
13 to 15
 
3 x 4 3/4

 
9
 
8 1/4
 
16 to 18
 
3 x 4 3/4

 
10
 
9   
 
17 to 19
 
3 1/2 x 5

 
12
 
11   
 
19 to 21
 
3 1/2 x 5 1/2

 
Paper Sizes for Shell Casings Single Break 

 
Shell Size (inch)
 
Number of turns/Paper weight
 
Length of Paper Sheet
 


 
3
 
3 turns of 30 to 40lb paper
 
1 x 24''
 


 
4
 
4 turns of 50 to 60lb paper
 
2 x 24 or 1 x 48'' 
 


 
5
 
5 turns of 60 to 70lb paper
 
3 x 24 or 2 x 36''
 


 
6
 
6 turns of 60 to 70lb paper
 
4 x 24 or 2 x 48''
 


 
8
 
8 turns of 70  to 90lb paper
 
4 x 48''
 


 
Lighter papers than those shown may be used but will require more turns to give the same final thickness of the casing as when using the thicker paper.

 
Paper Sizes for Paste Wrap  Single Break

 
Shell Size (inch)
 
Number of Turns/Paper wt
 
Length of Paper Sheet
 


 
3
 
3 turns of 30 to 40lb paper
 
1 x 24 inch
 


 
4
 
4 turns of 50 to 60lb paper
 
2 x 24 inch
 


 
5
 
5 turns of 60 to 70lb paper
 
3 x 24 inch
 


 
6
 
6 turns of 60 to 70lb paper
 
4 x 24 inch
 


 
8
 
8 turns of 70 lb paper
 
4 x 48 inch
 


 
Former and Disc Sizes for Hand Rolled Bottom Shots.
   A. Fulcanelli Pyrotechnica.1X

 
Report Size
 
Former Size
 
Disc Size
 


 
3
 
1 3/4
 
2 1/2
 


 
4
 
2 - 2 1/4
 
3 1/2
 


 
5
 
2 1/2 - 3
 
4 3/4
 


 
6
 
3 1/2 - 4
 
5 3/4
 


 
8
 
4 1/2
 
7
 


 
Typical Dimensions For Spiral Wound Salute Casings. 
  A.Fulcanelli  Pyrotechnica 1X

 
Salute Size
 
Casing Inside Diameter
 
Casing Outside Diameter
 
Case Wall Height

 
3
 
1 3/4
 
2 1/2
 
2 1/2

 
4
 
2 1/2
 
3 1/2
 
3

 
5
 
3 1/2
 
4 1/2
 
3 1/2

 
6
 
4 1/2
 
5 1/2
 
4

 
Spiking Pattern Vertical/ Horizontal Strands. For shells 3 to 5 inch a doubled strand of Good quality Flax or Hemp is sufficient (string should be pasted).
  A.Fulcanelli  Pyrotechnica. 1X

 
Shell Size (inch)
 
String Type
 
Vertical Strands
 
Horizontal Spacing

 
3
 
 Unwaxed Flax or Hemp
 
12/2
 
3/8 inch

 
4
 
Unwaxed Flax or  Hemp
 
16/2
 
3/8inch

 
5
 
Unwaxed Flax or Hemp
 
24/2
 
1/2 inch

 
6
 
Unwaxed Flax or Hemp
 
32/2
 
1/2 inch

 
8
 
Unwaxed Flax or Hemp
 
48/2 or 48/3
 
1/2 inch

 
Typical Spiking Patterns for Rinfasciature.  
  A. Fulcanelli  Pyrotechnica. 1X

 
Shell Size (inch)
 
First Spiking Side Strings
 
Second Spiking Side Strings
 


 
3
 
8
 
8
 


 
4
 
12
 
12
 


 
5
 
16
 
16
 


 
6
 
24
 
24
 


 
8
 
32 or 36
 
32 or36
 


 
Spolette Dimensions Single Break Shells.   
  A Fulcanelli  Pyrotechnica. 1X

 
Shell Size (inch)
 
Tube I.D
 
Tube O.D
 
Length (inch)
 
Powder Charge 

 
3
 
5/16
 
1/2
 
2
 
1 to 1 1/4

 
4
 
5/16 to 3/8
 
11/16
 
3
 
1 3/8

 
5
 
5/16 to 3/8
 
11/16
 
3
 
1 2/8 to 1 1/2

 
6
 
5/16 to 3/8
 
11/16
 
3
 
1 1/2

 
8
 
5/16 to 3/8
 
11/16
 
4
 
1 3/4

 
Delay Time for Time Fuse. (Initial fuse ignited by lift charge) 

 
Shell Size (inch)
 
Seconds Delay Time
 

 


 
3
 
2.5 to 3
 

 


 
4
 
3 to 3.5
 

 


 
5
 
4
 

 


 
6
 
5
 

 


 
8
 
5.5 to 6
 

 


 
These are typical times for single break shells. Multi-Break shells, Maltese style shells and shells with inserts or other effects may have longer or shorter timing than this.

 
Burst Charge Center Tube Sizes (canulle). 

 
Shell Size (inch)
 
Canulle Inside Diameter Inches
 
Wall Thickness
 


 
3
 
3/4 - 1
 
1/64"
 


 
4
 
1 - 1 1/4
 
1/64"
 


 
5
 
1 1/4 - 1 1/2
 
1/64"
 


 
6
 
1 1/2 - 2 1/4
 
1/64"
 


 7 

8
 
10

2 1/2
 

2 1/2 - 2 3/4

3 - 3/12
 
 1/64'' 

1/64"

1/64
 


 
Approx Size of Cut Stars According to Shell Size.

 
Shell size (inch)
 
Colour Stars
 
Tailed Stars
 


 
3
 
1/4  or smaller
 
1/4  - 3/8
 


 
4
 
1/4 - 3/8
 
 3/8 - 1/2
 


 
5
 
3/8 - 1/2
 
1/2 - 5/8
 


 
6
 
3/8 - 1/2
 
1/2 - 3/4
 


 
8
 
1/2 or larger
 
5/8 or larger
 


 
All sizes are approx and will depend on the formulation used, burning duration as well as the effect required.

 
Amount of Lift Charge for Single Break Shell  

 
Shell Size (inch)
 
Shell Contents
 
 
Weight 2FA  (oz)
 
Weight 2FA (gm)

 
3
 
color /salute
 
1
 
28

 
3
 
color/salute with inserts
 
1 1/4 to 1 1/2
 
35 to 42

 
4
 
color /salute
 
2
 
56

 
4
 
color/salute with inserts
 
2 1/2
 
70

 
5
 
color /salute
 
3 to 3 1/2
 
84 to 98

 
5
 
color/salute with inserts
 
4 to 5
 
112 to 140

 
6
 
color /salute
 
4 to 5
 
112 to 140

 
6
 
color/salute with inserts
 
4 1/2 to 6
 
126 to 168

 
8
 
color /salute
 
8 to 12
 
224 to 336

 
A basic rule of thumb is to allow 1 oz of 2FA per lb of shell weight up to 10lbs then 1/2 oz for every lb over 10lbs These amounts are based on using commercial 2FA powder such as Goex. If you are using a different grade or homemade lift the amounts needed will be significantly higher or lower than those in the table. Amount will also vary depending on the shells length, clearance in the mortar and the type of shell etc.

 
Rough Powder Formulation (Polverone) 
  A Fulcanelli  Pyrotechnica. 1X

 
Formulation
 
1
2
 
3

 

 
Part
 
%
 
Part
 
%
 
Part
 
%

 
Potassium Nitrate
 
18
 
68.6
 
20
 
65.6
 
24
 
65.8

 
Airfloat Charcoal
 
4
 
15.2
 
5
 
16.4
 
6 1/2
 
17.7

 
Sulphur
 
3
 
11.4
 
4
 
13.1
 
4
 
11.0

 
Dextrin
 
1 1/4
 
4.8
 
1 1/2
 
4.9
 
2
 
5.5

 
Kraft Paper Weight and Calipers

 
Paper weight
 
Caliper (thickness)
 

 


 
30 lb
 
.003''
 

 


 
40 lb
 
.004''
 

 


 
50 lb
 
.005''
 

 


 
60 lb
 
.006''
 

 


 
70 lb
 
.007''
 

 


 
90 lb
 
.009''
 

 


 
Spolette Tube Dimensions and Powder Charges for Single Break Shells.
  A. Fulcanelli  Pyrotechnica. 1X

 

 
Tube I.D
 
Tube O.D
 
Tube Length
 
Powder Charge

 
3 inch single break
 
1/4 to 5/16''
 
.550''
 
1/1/2 - 2''
 
1 - 1 1/4

 
4 inch single break
 
5/16 - 3/8 
 
11/16
 
3''
 
1 3/8

 
5 inch single break
 
5/16 to 3/8
 
11/16
 
3''
 
1 3/8 - 1 1/2

 
6 inch single break
 
5/16 to 3/8
 
11/16
 
3''
 
1 1/2

 
7 inch single break
 
5/16 to 3/8
 
11/16
 
4''
 
   1 1/2 - 1 5/8

 
8 inch single break
 
5/16 to 3/8 
 
11/16
 
4''
 
1 3/4
 

 
Because  increment amounts and ramming force vary from one worker to another exact timings in seconds are not possible but as a rough guide 1 inch of powder core is equal to 3 seconds.

 
 
Initial and Intermediate Spolette Tube Dimensions/Powder Charges for Multibreak  Shells.
  A. Fulcanelli  Pyrotechnica. 1X
 
Shell Size Inches
 
Tube I.D
Tube OD
 
Tube Length
 
Initial Spolette
 
Charge
 
 Intermediate
Spolette
 
Charge
 
3
 
5/16
 
.55''
 
2''
 
2 to 3 break
 
1 inch
 
2 to 3 break   
 
   3/4''
 
3
 

 

 

 
4 to 5 break
 
3/4 inch
 
4 to 5 break 
 
   1/2''
 
4
 
5/16
 
.55''
 
2''
 
2 to 3 break 
 
1 inch
 
2 to 3 break
 
   3/4''
 
4
 
5/16 - 3/8
 
11/16
 
2 1/2"
 
4 to 5 break 
 
3/4 inch
 
4 break 
 
1/2 -3/4''
 
4
 

 

 

 
over 5 break 
 
3/4 inch
 
over 5 break 
 
   1/2''
 
5
 
5/16 - 3/8
 
11/16
 
2 1/2"
 
  2 break 
 
1 1/4 inch
 
2+3 break 
 
   3/4''
 
5
 

 

 

 
3 break 
 
1 inch
 
4 break 
 
1/2 -3/4''
 
5
 

 

 

 
4 + 5 break 
 
3/4 inch
 
over 5 break
 
1/2''
 
6
 
5/16 - 3/8
 
11/16
 
2 1/2"
 
2 break 
 
1 1/4 inch
 
2 + 3 break 
 
2 + 3 break  3/4''
 
6
 

 

 

 
3 break 
 
1 inch
 
4 break 
 
1/2 -3/4''
 
6
 

 

 

 
4 + 5 break  
 
3/4 inch
 
over 5 break 
 
1/2''
 
8
 
5/16 - 3/8
 
11/16
 
3 1/2-4"
 
2 break 
 
1 1/2 inch
 
2 +3 break 
 
3/4''
 
8
 

 

 

 
3 break 
 
1 inch
 

 


 
Size and Number of Comet Rings According to Shell Size

 
Shell Size
 
Comets Per Ring
 
Comet Size O.D
 


 
5''
 
10
 
1''
 


 
5''
 
9
 
1 1/8''
 


 
5''
 
8
 
1 1/4''
 


 
6''
 
12
 
1 1/8''
 


 
6''
 
10
 
1 1/4''
 


 
8''
 
14 loose
 
1 1/4''
 


 
8''
 
15 tight
 
1 1/4''
 


 
Minimum Fireworks Safe Display Site Radius.

 
Shell Size
 
Display Site Radius
 

 


 
< 3 in.
 
140 ft.
 

 


 
3 in.
 
210 ft.
 

 


 
4 in.
 
280 ft.
 

 


 
5 in.
 
350 ft.
 

 


 
6 in.
 
420 ft.
 

 


 
7 in.
 
490 ft.
 

 


 
8 in.
 
640 ft.
 

 


 
10 in.
 
700 ft.
 

 


 
12 in.
 
840 ft.
 

 


 
Minimum Mortar Tube Lengths for Shells.  

 
Mortar ID (in.)
 
Single Break
 
Double Break
 
Up to 4-Break

 
3
 
15
 
18
 
21

 
4
 
20
 
23
 
27

 
5
 
24
 
28
 
32

 
6
 
28
 
32
 
37

 
8
 
34
 
40
 
46

 
10
 
40
 
46
 
54

 
12
 
46
 
52
 
62

 
Shell Burst Heights.  

 
Shell (in)
 
Size (mm)
 
Height (ft)
 
Height (m)

 
3
 
76
 
400
 
120

 
4
 
102
 
500
 
150

 
5
 
127
 
600
 
180

 
6
 
152
 
700
 
210

 
8
 
203
 
900
 
270

 
10
 
254
 
1050
 
320

 
12
 
305
 
1150
 
350

 
These  are approximate values and will vary according to the weight of the shell, the amount and grain size of your lift powder as well as the length of the mortar. It should be remembered that some types of shells are designed to burst during accent eg Multi-Break Maltese Cylinder shells.

 
United States  Black Powder Grades
  R. Lancaster 1972

 
Type
 
U.S Sieve Number
 

 


 
2FA
 
4/12
 

 


 
3FA
 
10/16
 

 


 
4FA
 
12/50
 

 


 
5FA
 
20/20
 

 


 
6FA
 
30/50
 

 


 
7FA
 
40/100
 

 


 
Meal D
 
+50
 

 


 
Fine Meal
 
+100
 

 


 
Extra Fine Meal
 
+140
     
Twine Length to Spike Single Break Shells
         Shell Size                         Approx Twine Length Needed
 3" (2 1/2 "long)
      14 feet
4" (3" long)       19 feet
5" (4" long)       34 feet
6" (5" long)       51.5 feet
8" (6" long       94.5 feet

 
Copyright Bangkok Pyro Company Thailand 2011