SDZ Construction: M242 25mm Gun Inter-service Resident Range Safety Course (Intermediate)

SDZ Construction:M242 25mm GunInter-service Resident Range Safety Course (Intermediate)

August 2003

M2A3 Bradley Fighting Vehicle

August 2003

Marine Corps Light Armored Vehicle (LAV) with the M242 25mm gun

M242 25mm Gun

August 2003

25mm Ammunition

M792HEI-T

M791APDS-T

M793TP-T

M794 M910

August 2003

Weapon:

Ammo Type:

Impact Media:

Distance X:

Angle P:

Distance W:

Area A:

Area B:

Map Scale:

Map Sheet:

Map Series:

Map Edition:

Date:

Name:

Legend for 25mm Systems

August 2003

Constructing a 25mm SDZConstruct 25mm system SDZ for the M242 25mm gun firing the M792 (HEI-T) cartridge into armor.

Dimensions of the SDZ for this weapon system are given in DA-PAM 385-63, Chapter 12, Table 12-5.

Plot the firing point, target, and then establish the gun target line.

August 2003

Plot the firing point.

Establish the gun target line.

Plot the target.

August 2003

From Table 12-5, find Distance X (armor).

Distance X = 6379m

Annotate Distance X on the legend.

At the firing point, measure 5° with a protractor from the left and right of the gun target line.

5°

(ˆ 6400m)

Dis

tan

ce

X

August 2003

Draw tic marks as shown.

To establish the Dispersion Area, draw a straight line from the firing position through each tic mark out to Distance X.

This completes the Dispersion Area. 5°

DispersionArea

Dis

tan

ce

X

August 2003

For the Ricochet Area, on Table 12-5, find the measurement for Distance W (armor).

Lightly draw lines perpendicular to the limits of the Dispersion Area.

Distance W =(ˆ 1400m) Dispersion

Area

1373m

Dis

tan

ce

X

August 2003

Draw tic marks at the measurement for Distance W on the lines just drawn.

DispersionArea

Draw a straight line through the tic marks.

On Table 12-5, find the measure-ment for Angle P.

Angle P = 28°P P

Dis

tan

ce

X

August 2003

Draw tic marks.

At the firing point, measure 28° from the left and right limits of the Dispersion Area to establish the Ricochet Area.

DispersionArea

28°

P P

Dis

tan

ce

X

August 2003

This completes the Ricochet Area.

Draw a straight line from the firing point through each tic mark just drawn.

DispersionArea

28°

P P

Dis

tan

ce

X

August 2003

Draw a straight line from the firing point through each tic mark just drawn.

DispersionArea

RicochetArea

Annotate the Ricochet Area (Distance W) on the legend.

This completes the Ricochet Area.

Dis

tan

ce

X

August 2003

DispersionArea

RicochetArea

From the firing position, scribe an arc between the left and right limits of the Ricochet Area. Use Distance X as the radius.

Erase unnecessary lines.

Dis

tan

ce

X

August 2003

DispersionArea

RicochetArea

From the firing position, scribe an arc between the left and right limits of the Ricochet Area. Use Distance X as the radius.

On Table 12-5, find the measure-ment for Area A.

Area A = 300m

Erase unnecessary lines.

Dis

tan

ce

X

August 2003

Draw straight lines through the tic marks just drawn.

Lightly draw lines perpendicular to the limits of the Ricochet Area.

DispersionArea

RicochetArea

Draw tic marks at the measurement for Area A.

DispersionArea

RicochetArea

Dis

tan

ce

X

August 2003

Draw tic marks.

At the firing point, measure 25° from the left and right limits of the Ricochet Area.

From the firing point, draw straight lines through the tic marks.

DispersionArea

RicochetArea

25°

DispersionArea

RicochetArea

Dis

tan

ce

X

August 2003

On Table 12-5, find the measurement for Area B.

Area B = 400m

Lightly draw a line that extends the gun target line from Distance X.

DispersionArea

RicochetArea

25°

Verify that the measurement for Distance X is correct; then place a tic mark at the measurement for Area B.

DispersionArea

RicochetArea

Dis

tan

ce

X

August 2003

RicochetArea

This completes Areas A and B.

From the firing point, scribe an arc from the right and left limits of Area A using the measure-ment for Area B as the radius.

25°

DispersionArea

RicochetArea

Dis

tan

ce

X

August 2003

RicochetArea

This completes Areas A and B.

Annotate Areas A and B on the legend.

From the firing point, scribe an arc from the right and left limits of Area A using the measure-ment for Area B as the radius.

To complete the SDZ, erase all unnecessary lines.

DispersionArea

RicochetArea

Area A

Area B

Dis

tan

ce

X

August 2003

RicochetArea

From the firing point, scribe an arc from the right and left limits of Area A using the measure-ment for Area B as the radius.

DispersionArea

RicochetArea

Area A

Area B

Dis

tan

ce

XThis completes Areas A and B.

Annotate Areas A and B on the legend.

To complete the SDZ, erase all unnecessary lines.

August 2003

Weapon: M242 25mm Gun

Ammo Type: M792 (HEI-T)

Impact Media: Armor

Distance X: 6379m (ˆ6400m)

Angle P: 28°

Distance W: 1373m (ˆ1400m)

Area A: 300m

Area B: 400m

Map Scale: 1:50,000

Map Sheet:

Map Series:

Map Edition:

Date:

Name:

Legend for 25mm Systems