A gun’s proof mark provide the correct information to allow you to choose a cartridge that can be used safely in your particular gun.
Traditionally, different pellet sizes in lead shot have been favoured for different types of shooting, such as:
Recent research, however, may result in recommended shot sizes changing, generally towards larger pellets than were used in the past.
Each non-lead type has different ballistic characteristics, which means that pellet sizes may need to change for these materials to achieve pattern density and striking energy levels sufficient to ensure consistently clean kills.
In particular, where the material is less dense than lead, and so has less kinetic energy, it is necessary to use a larger size shot – for example, if steel is used then at least two sizes larger (i.e. for lead no.6 use steel no.4 or larger); if bismuth is used then at least one size larger (no.3 or larger in place of lead no.4).
While the traditional game load has long been 30g or 32g (11/16 oz and 11/8 oz) of no.6 shot nowadays game shooters are using more no.5 or larger shot.
- Geese – BB or No 1’s
- Large Ducks – 3’s or 4’s
- Pheasants – 3’s or 4’s
- Woodcock – 5’s
- Pigeon 5’s or 6’s
- Small Ducks – 4’s – 5’s
- Snipe – 6’s or 7’s
In Bismuth increase the shot size by one from the traditional lead sizes quoted above.
Remember – a heavy load does not necessarily increase the effective range of a shotgun.