C1, FM 6-40/MCWP 3-1.6.19
Change HEADQUARTERS
No.1 DEPARTMENT OF THE ARMY
Washington, DC, 1 October 1999
Tactics, Techniques, and Procedures for
FIELD ARTILLERY
MANUAL CANNON GUNNERY
FM 6-40/MCWP 3-16.4, April 1996, is changed as follows:
1. Change the following paragraphs or sections (changes are in bold type):
Replace Paragraph 6-1, Page 6-1 with the following:
6-1. Description
A firing chart is a graphic representation of a portion of the earth's surface used for determining
distance (or range) and direction (azimuth or deflection). The chart may be constructed by using a
map, a photomap, a gridsheet, or other material on which the relative locations of batteries, known
points, targets, and observers can be plotted. Additional positions, fire support coordinating measures,
and other data needed for the safe and accurate conduct of fire may also be recorded.
Replace Step 5, Table 6-6, Page 6-19 with the following:
5
Place a plotting pin opposite the number on the azimuth scale (blue numbers) on the arc of the
RDP corresponding to the last three digits of the azimuth in which the arm of the RDP is
oriented. The location of the pin represents a temporary index and will not be replaced with a
permanent index. The value of the pin is the value of the first digit of the azimuth in which the
arm o f the RDP is oriented. Use the rules outlined in step 4 of Table 6-5 to determine where
the pin should be placed. In Figure 6-15, the azimuth of lay is 1850, so the RDP has been
oriented east (1600 mils).
Replace Figure 7-1, Page 7-1 with the following:
STANDARD CONDITIONS
WEATHER
1
AIR TEMPERATURE 100 PERCENT (59° F)
2 AIR DENSITY 100 PERCENT (1,225 gm/m
3
)
3NO WIND
POSITION
1 GUN, TARGET AND MDP AT SAME ALTITUDE
2 ACCURATE RANGE
3 NO ROTATION OF THE EARTH
MATERIAL
1 STANDARD WEAPON, PROJECTILE, AND FUZE
2
PROPELLANT TEMPERATURE (70° F)
3 LEVEL TRUNNIONS AND PRECISION SETTINGS
4 FIRING TABLE MUZZLE VELOCITY
5NO DRIFT
LEGEND: gm/m
3
- grams per cubic meter
