powder charge is located in the cone-
the impact of a firing pin. The primer, in
turn, ignites the igniter which ignites the
shaped opening on the inner face of the
cartridge head.
propellant.
(3) Small cartridges with easily ignited
b. Cartridge Case.
propellants, such as the cartridge shown
(1) Design and development time is reduced
in figure 27, do not ordinarily contain
whenever possible by using existing
separate igniter chambers. Instead, the
cartridge cases. Table VIII presents data
(black powder) igniter is mixed with the
on cases already developed. The letters
propellant. In figure 26, the black
in the column headings refer to the
lettered dimensions in figure 27.
Figure 27. Typical small cartridge.
Figure 26. Typical large cartridge.
Table VIII. Sizes of Existing Cartridge Cases
Head
Length
Shoulder
Propellant
Approximate
Body diameter D (in.)
diameter
L (in.)
H (in.)
chamber †
volume
Cartridge ‡
(in.3)
B (in.)
M (in.)
0.550................................................................
0.710
7/8
0.26
1/2
0.1
M67
0.550................................................................
0.710
1 3/8
0.26
1
0.2
M38
0.550................................................................
0.710
1 5/8
0.26
1 1/4
0.2
M42
0.687................................................................
0.875
1.075
0.26
1/2
0.2
T292
0.687................................................................
0.875
2
0.26
1 1/2
0.5
M46
0.687................................................................
0.875
2 5/16
0.26
1 13/16
0.6
M70
0.710................................................................
0.880
1 3/32
0.26
1/2
0.2
T297
1.085................................................................
1.245
2 7/8
0.26
2 3/16
1.8
M31A1
1.245................................................................
1.390
755
0.26
1/8
0.1
T298E1
1.245................................................................
1.390
1 7/16
0.26
3/4
0.8
M69
1.245................................................................
1.390
1 11/16
0.27
15/16
0.9
M29A2
1.245................................................................
1.390
2.02
0.26
1 1/8
1.3
T299
1.245................................................................
1.390
2 3/8
0.26
1 9/16
1.7
T254
1.245................................................................
1.410
6 1/8
0.26
5 7/16
6.1
M37
1.495................................................................
1.660
4 7/16
0.30
3 5/8
6.0
M30A1
1.495................................................................
1.660
4 3/4
0.28
4
6.6
M28A1
1.495................................................................
1.660
8 7/8
0.24
8 3/16
13.5
M36
1.745................................................................
1.910
6 7/8
0.26
6 3/16
13.9
T125
† Assuming a standard cartridge head (no delay element).
‡ One of the cartridges in which the case is used.
35
