There has been debate for years over the optimum shot size. Diggory Hadoke tries to settle the matter for once and for all.
- We choose shot to produce an acceptable compromise for the shooting we do and the gun we use.
- The ideal we seek is a killing pattern that covers the target and individual pellets in that pattern that hit with sufficient force to impart shock and do lethal damage.
In 1833 Lieutenant Colonel Peter Hawker told readers: “A common-sized gun will shoot No. 7 shot better than any other shot… I am confident that had you, for a whole season, no other sized shot, you would find that you had killed more game.” Hawker mostly shot over dogs, what we would call walked-up shooting today.
The pros and cons of shot size
- Small shot produces a fuller pattern because there is more of it in the cartridge (assuming the same weight load).
- Larger shot carries momentum and energy for longer distances and penetrates deeper. However, with fewer pellets in the pattern, there will be greater space between each one.
- Gough Thomas called these limiting factors “pattern at the expense of energy” (small shot) and “energy at the expense of pattern” (large shot).
- The balance to be struck is one between pattern and penetration.
- Hitting a bird with lots of tiny shot that doesn’t penetrate the skin won’t kill it and hitting a bird with one pellet that breaks its leg won’t kill it either.
- You select shot sizes to ensure you have enough shot to hit one or more vital organs and produce sufficient shock to kill it. That shot needs to penetrate deep enough to enter vital organs and break bones.
- At closer ranges, small shot has sufficient momentum to penetrate. Only at longer ranges does it lose energy.
- At short range, large shot remains close enough together to make multiple hits, so pattern is not a problem. The problems manifest when you extend the range. Small shot may not penetrate sufficiently and large shot may leave too many holes in the pattern.
The consequences of choosing the wrong shot size
- Fewer clean kills (desired result)
- Smashed game (hit with too many shot pellets)
- Missed or wounded game (either from failure of pattern or penetration).
The ideal shot size?
Major Gerald Burrard decreed that the ideal shot size should be that which carries sufficient penetration five yards further than the point at which a pattern becomes too open.
He explained: “A smaller size of shot than No.6 confers no possible advantage in range or killing power… [and] may cause wounded birds at long range owing to lack of penetration, and result in plastered birds at close range. It is probable that No.6 comes closest to the ideal.”
However, he conceded that in practice the difference between No.5, No.51⁄2 and No.6 shot on pheasants at ordinary game ranges (up to 40 yards) was small enough not to really matter.
For partridge or pheasant, Thomas believed that No.6 shot was the best general size to use. Burrard agreed: “33 grains of powder and 11⁄16oz of No.6… probably as good an all-round load as any… will kill partridges slightly beyond 40 yards and bigger birds up to 45 or 50 yards.”
Gunmaker Tom Purdey advised in 1936: “The best load for the average sportsman would be 1oz or 1 1⁄6oz of No.6 shot. The average shooter cannot do better than use No.6 shot for all his regular shooting, and if he holds his gun straight he will kill all his game cleanly and well with this shot.”