Subadar Prag Tewarri, bidding them load with ball,
Halted a dozen rifles under the village wall;
Sent out a flanking-party with Jemadar Hira Lal.
(from) The Grave of the Hundred Head - Rudyard Kipling
In this context ball refers to one of a number of related types of ammunition.
In modern usage ball ammunition refers to a standard bullet with no special features. This refers back to the ball-shaped rounds fired by muskets and early rifles - and the similar but much larger rounds fired by early cannon, even though almost all modern rounds use some form of conoidal bullet. The term is also applied to various intermediary types of which the most famous is probably the minie ball.
Materials of manufacture vary - a modern round can be cast from all sorts of metals, including steel but more commonly various alloys of lead. Earlier examples were made from lead (for small arms) and stone or cast iron for ordnance. Composite rounds are also entirely normal - for example the "FMJ" or "full metal jacket" round where a soft lead or lead alloy projectile is protected from deformation by a full length sheath of harder metal.
Game and Story Use
- This will normally be the default type of ammunition that gives whatever the basic stats are in the weapons table - other types of ammo will then modify these stats.
- Many game systems more or less ignore the great differences in performance even within the same type of ball - the same calibre can behave very differently in top of the line civilian match-grade rounds from the developed world and third world wartime ammo.
- In most militaries, this and tracer are probably all you get - perhaps with some kinetic armour piercing thrown in. Most of the "fun" stuff is prohibited in order to comply with international conventions on fragmenting ammunition and other mutilating weapons.