Who needs bigger balls?

What is the ideal shot size for game shooting?

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Gunsmithing & Technical|November 2019

Shot size has been debated for as long as guns have been throwing clusters of small lead balls at flying birds. Everyone has a pet theory and fashions wax and wane but when we break the conundrum down to its basic components we have two key issues to address.

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 which covers the target and individual pellets in that pattern that hit with sufficient force to impart shock and do lethal damage.

 Hawker told readers; ‘A common sized gun will shoot No.7 shot better than any other…. '

There are pros and cons to 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 that will ensure you have enough shot covering your bird to hit one, or more, vital organ and produce sufficient shock to kill it. That shot needs to penetrate deep enough to enter those 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 results of choosing the wrong shot size can be categorised as: A) Clean Kills (the desired result), B) Smashed Game (hit with too many shot pellets) and C) Missed or Wounded Game (either from failure of pattern or penetration).

Major 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. Essentially, maintaining that failure of pattern happens before failure of penetration.

For partridge or pheasant, Gough Thomas opined that No.6 shot was the best general size to use. Burrard agreed: ’33 grains of powder and 1 1/16 oz of No.6… probably as good an all-round load as any…Will kill partridge slightly beyond 40 yards and bigger birds up to 45 or 50 yards.’

...’33 grains of powder and 1 1/16 oz of No.6… probably as good an all-round load as any…

Gunmaker, Tom Purdey (in 1936) also advised; ’The best load for the average sportsman would be 1 oz or 1 1/6 oz 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.’

Burrard further explained: ‘a smaller size of shot than No.6 confers no possible advantage in range or killing power… may cause wounded birds at long range owing to lack of penetration and results in plastered birds at close range’. ‘It is probable that No.6 comes closest to the ideal’.

However, he concluded that the difference, practically, between No.5, No.5 1/2 and No.6 shot on pheasants at ordinary game ranges (up to 40 yards) was small enough not to really matter.

By the 1950s, smaller shot was in vogue in the UK, with gunmaker Gallyon of Cambridge advising readers of his catalogue ‘The highest pheasant, or the toughest duck, or the strongest flying grouse is more likely to be bagged when struck by half-a-dozen No.7 pellets than by the equivalent weight in fours or fives.’

The modern consensus is that in order to reliably kill a bird (concentrate on pheasant and partridge to keep it simple) it is desirable to penetrate it with at least three pellets, in order that at least one of them will be fatal. ‘Normal’ conditions consider the shot to be taken within forty yards with a gun choked Improved Cylinder. For this, 30g of No.6 is the optimal load.

However, it becomes more complicated when we consider longer-range shooting. Choke extends your range. So, if you have a forty-yard killing pattern with Improved Cylinder and 30g of No.6 shot, you can extend the killing range of the same load by using Half Choke.

However, as range extends, so the lighter pellets lose energy and, while choke may keep the pattern together for longer, it won’t add to penetrative power. For that you need weight. So; bigger shot.

If you are engaging birds beyond forty-five yards, changing to No.5 is sensible. However, if you do so, in order to fill your pattern, you need more shot or more choke. Your 30g of No.6 through Improved Cylinder at forty yards should be changed to 32g No.5 if you are expecting fifty-yard shots.

At longer range, you need tighter chokes, within the limits of performance. Once chokes go beyond forty thou” constriction, patterns start to get worse; and very large shot patterns very erratically.

However, the experience of today’s, consistently effective, long-range pheasant Shots reflects the principle that, as you go further out, you need to use bigger pellets to retain penetration. You need more pellets to fill the pattern and tight chokes to keep it together at extreme ranges.

It is no surprise to hear of No.3 or No.4 shot and loads of 36g or more employed to engage extremely high pheasants.

I advise anyone who asks, to use fibre-wadded 28g or 30g loads of No.6 for all their general shooting with traditional British 12-bores, unless shooting snipe, for which No.7 provides sufficient penetration but with the fuller pattern desirable for a small bird at normal ranges.

Do not overlook the importance of quality components. The return of wool as a premium wadding material, by Gamebore, is interesting, as it provides excellent obduration and cushioning properties, without which no shot load, of whatever size, is going to produce its best results. In short, don’t obsess about the optimal shot size and then buy cheap cartridges.

Game shots are often asked not to use plastic wad cartridges but there are now fully water-degradable versions arriving on the market, made from natural products, which not only reduce shot deformation and protect the shot as it travels down the barrel, but which leave one’s conscience clear that we sportsmen are not contributing to the plastic littering of the countryside we deplore in others.

Published by Vintage Guns Ltd on (modified )

Gunsmithing & Technical|November 2019

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