How much shot? What size? How fast? What wad? These are some of the crucial questions you need to ask when choosing clay cartridges.
Q. How much shot?
A. For the ruling on maximum shot loads and sizes for each discpline, take a look at the Clay Pigeon Shooting Association’s Booklet.
For the British domestic disciplines the limit is 28 grammes, which is just a fraction less than an ounce. Participants in the international discipline of FITASC Sporting used to be allowed to use up to 36gr (1¼oz), but their limit has now been dropped to 28gr. Other international disciplines, such as Olympic Trap, require a load of 24gr, which is about 7/8oz.
These are the maximum loads allows but there is nothing to stop you using loads lighter than this. Lighter loads, like the 24gr, are usually easier on the shoulder which could be beneficial to those who are wary of recoil or slightly built.
All of the above, of course, assumes that you shoot a 12-bore. Twenty-bore shooters can choose from ranges of cartridges loaded with 21gr (3/4oz), or 24gr (7/8oz). You can also buy 20-bore cartridges in 28gr, although when shooting a load as heavy as this most shooters would be happier with a 12-bore, which would be heavier and therefore soak up the recoil better.
Q. What size shot?
A. Rules apart, all the choices you make on shot size will be a compromise. Large shot goes further and hits harder but can produce a sparse pattern. Small shot won’t go as far or hit as hard but produces dense patterns.
For skeet, by rule, you must use either size 9 or size 10 shot. This is no bad thing because it’s a game of fast, crossing targets which are relatively close, so with the small shot required, the shooter gets the best possible pattern. For most other competitions, the biggest shot you may use is No.6, which is the most commonly-used bird shot. Again, see the CPSA booklet for the definitive ruling.
The sporting disciplines are different to skeet in that targets are presented at all practical ranges. For most club targets, sizes 7½ or 8 will give the best chance at most targets. However you should change things around when targets get more difficult. . For instance, if a stand presenting doubles on report starts with a relatively close, incoming target, then gives a fast-retreating target, you can always load the first barrel with a skeet shell, and tackle the second target with a relatively potent trap cartridge carrying size 7.
The trap disciplines are usually shot with sizes 7 or 7½, but again there is nothing to stop you using small shot in the first barrel and larger shot in the second to tackle the more distant targets.
Q. What about speed?
A. To be accurate, consistency is more important than sheer muzzle velocity. A good competition cartridge generates the same muzzle velocity within a few feet per second, and some of the best clay-shooting cartridges have not been that spectacularly fast. So it is better to pick a cartridge you are comfortable shooting 100 plus shots a day rather than the one with an advertised extremely high muzzle velocity. By ‘very high’ we mean a muzzle velocity of over 1,400 feet per second, or 420 metres per second if you prefer, and you may be happier with a cartridge generating 1,300ft/sec (390m/sec).
If the shooting ground has a bad noise problem, you can get subsonic ammunition, which generates a muzzle velocity of around 1,050ft/sec (390 m/sec). Subsonic cartridges generate lower noise levels at the muzzle, and also avoid the supersonic ‘crack’ which merges with the bang. These cartridges are useful for training. Some pupils flinch when they hear a loud bang or equate cartridge noise with recoil.
Q. What about wad material?
A. Wad in a cartridge is there to provide a gas-tight seal between the shot charge and the large volume of hot, rapidly-expanding gas generated as the powder burns. Cartridges assembled with plastic shot cup wads generally throw tighter, more accurate patterns than those assembled with fibre wads.
However plastic wad can be dangerous to animals, blocking up their digestive tract and on some clay shoots wads are likely to fall on fields where farm stock graze.
The solution is to use fibre-wadded cartridges and the patterning qualities of such loads has increased markedly in recent years.
You should always call ahead when visiting a shooting ground to see if there is a fibre-wad rule.
Finally fibre-wadded cartridges can be more noisy than their plastic-wadded equivalents, and they may also throw slightly more dispersed patterns.