BULLET CALIBER CALCULATIONS
BACKGROUND INFORMATION
Caliber refers to the diameter of a bullet or the inside of a firearm's barrel.
Caliber is usually expressed in hundredths of an inch or in millimeters.
+
Example: 50 Caliber = 50/100 of an Inch
1 in = 25.4 mm
1 mm = 0.039 in
Circumference = 2πr
PROBLEMS TO SOLVE
1. Being sold at an army surplus store is a pen gun. The pen gun fires a .22 caliber cartridge with a
short barrel that has no rifling, so it must be shot at very close range such as 2ft or 3ft to do
damage. What is the pen gun's diameter in inches?
ee
2. Used commonly as a sporting rifle cartridge, a .243 Winchester bullet would be what caliber?
-243
3. The ring pistol was invented in the 19th century by a French gunsmith. The bullets it fired
measured about 4 mm in diameter.
a. How many inches in diameter were the bullets?
10.158in
-4x0.039
b. What is the circumference of a bullet from the pen gun?
L=πd= TT.(0.22)
0.69lin
4. Since 1934, the .357 S&W Magnum has been a revolver cartridge that is excellent for hunting.
Bullets for a .357 Magnum are how many millimeters in diameter?
.357x25.4 =
9.06jmm
5. Heavy Machine Guns were used extensively in battles and conflicts such as World War II, the
Korean War, and the Vietnam War. Calculate the circumference of the barrels of the following
heavy machine guns:
a. Browning .50 Caliber Machine Gun
(=TT(.50)
1.57in
b. MG-42 (fired 8 mm Mauser rounds)
(= π (8) = 11
25.13in
c. .303 Bren (British Model)
C=TI (0.303)
0.95zin
6. Shotguns are classified according to gauge, which refers to how many lead spheres (each of
equal diameter to the bore) amount to 1 lb. in weight. For a 12-gauge shotgun, it would take 12
spheres the size of the shotgun's bore to 1 lb. The smaller the gauge is, the wider the barrel.
a. For a 16-gauge shotgun, how many lead spheres would equal 3 lbs. In weight?
16x3 spheres
b. Would a 16-gauge shotgun have a bigger or smaller barret than a 12-gauge shotgun?
Explain.
The 16 gauge IS smaller since the
higher the guage is the smaler the
barrel claimeter
