Common Ammo

Description of the table columns:

Ammo 
The type of ammo. For ammo that is cut by the barrel, such as spuds, this gives a typical length of the ammo. The length of the ammo and the barrel diameter determine the actual size of the ammo. For spuds, there is more than one way to cut the shell.
Mass 
The mass of the ammo in ounces (oz.) and grams.
Diameter 
The diameter of the ammo in inches (") and centimeters (cm). For ammo that is cut by the barrel, such as spuds, this is the barrel diameter. For ammo that is not cut, such as golf balls, this is the ammo's normal diameter.
Cd 
Coeficient of drag. The Cd of a particular ammo is usually dependent on the velocity of the ammo and whether or not it is spinning or tumbling.
Terminal Velocity 
The maximum velocity the ammo will reach when dropped, in air, form a great height.
Barrel 
Suggestions as suitable barrels for the particular ammo. Primarily for ammo that has a defined size, such as a tennis ball.
Other Info 
Various other bits of information concerning the ammo.

Table Notes

  1. The Cd values for the various sport balls (tennis ball, golfball ...) were calculated based on their terminal velocities using the equation Cd=2mg/(vterminal2) with g=9.8m/s and ρ=1290g/m3. The terminal velocities were from Terminal Velocity Teachers Notes and A Penny in Free Fall.
Common Spud Gun Ammo
Ammo Mass Diameter Cd Terminal
Velocity
Barrel Other Info
Fruit + Vegetables
half Potato, (2" Long) 2.5 oz., 72g 1.59", 4.04cm - - 1.5" SCH 40
  • density ~1.1g/cm3
half Potato, (2" Long) 5.0 oz., 120g 2.05", 5.21cm - - 2" SCH 40
  • density ~1.1g/cm3
full Potato, (4" Long) 5.1 oz., 140g 1.59", 4.04cm - - 1.5" SCH 40
  • density ~1.1g/cm3
full Potato, (4" Long) 10 oz., 240g 2.05", 5.21cm - - 2" SCH 40
  • density ~1.1g/cm3
Apple, 4.2 oz., 110g 2.05", 5.21cm - - 2" SCH 40
  • density ~0.95g/cm3
Citrus Fruit, 3.5 oz., 100g 2.05", 5.21cm - - 2" SCH 40
  • density ~0.9g/cm3
Balls
Ping-Pong Ball 0.095 oz., 2.7g 0.95", 2.51cm 0.460 <br\> (note 1) 9m/s, 30fps - -
Roll-on deodorant ball 0.095 oz., 5g 1.49", 3.80cm - - 40mm 10bar PVC (UK) -
Small pool ball 1.76 oz., 50g 1.49", 3.80cm - - 40mm 10bar PVC (UK) -
Golf ball 1.59 oz., 45g 1.68", 4.27cm 0.299 <br\> (note 1) 40m/s, 132fps - -
Tennis Ball 2.08 oz., 59g 2.56", 6.5cm 0.283 <br\> (note 1) 31m/s, 102fps
  • 2.5" SCH 40
  • 2.5" SDR 21
  • 2.5" SDR 26
-
Baseball 5.1 oz., 145g 2.9", 7.4cm 0.290
(note 1)
42m/s, 138fps - -
Basketball 21.2 oz., 600g 9.5", 24.1cm 0.500
(note 1)
20m/s, 66fps - -
Ball Bearings (BBs, Airsoft, Paintballs...)
0.177" Copper/Steel BB 0.0116 oz, 0.33g 0.177", 0.45cm - - - -
6mm Airsoft 0.0071 oz., 0.20g 0.23", 0.6cm - - - -
.68" Paintball 0.1 oz., 3.2g 0.68", 1.75cm - -
  • 0.5" SDR 13.5
  • 0.5" PN15 (UK)
  • 0.75" SCH 120
-
.61" glass marble 0.17 oz., 5g .61", 1.5cm - - 18mm copper -
Batteries (Diameter and mass vary slightly by brand)
AA ~0.98oz., ~28g ~0.55", ~1.4cm - - 15mm copper Outer plastic and metal wrapping must be removed.

Diameter varies by brand, cheaper is usually narrower

AAA ~.49 oz., 14g .39", 1 cm - - 15mm copper -
C 2.4-2.6 oz., 68-74g 0.996", 2.53cm - - 28mm copper
  • 2" (5.1cm) long
D ?? oz., ??g ?", ?cm - - - -
Other Things
12g CO2 Cartridge
(empty)
1.05 oz., 30g 0.73", 1.85cm - -
  • 0.75" SCH 40 PVC
  • 22mm Copper pipe
-
Ice ?? oz., ??g ?", ?cm - - - -
Pycrete ?? oz., ??g ?", ?cm - - - -
Film Canister 0.5oz., 12g 1.45", 3.7cm - -
  • 1.25" SCH 40
  • 40mm 10bar
Fits better with the right sized lid, still very good otherwise
Soda Can 13.0 oz., 369g
(water filled)
2.6", 6.6cm - - -