The diabolo airgun pellet
Airgun pellets are usually made in the diabolo form – a shape named after the traditional juggling game. The game of diabolo – from Latin diabolus (devil) – involves the tossing and manipulation of a two-headed bobbin, using a string stretched between two sticks. An earlier name for the game was “devil on two sticks”.
An airgun pellet takes on the general shape of the two-headed bobbin, with a solid head, wide skirt, and narrow waist. The rim of the skirt engages snugly with the rifled bore, creating a strong spin for a flat trajectory. The pellet’s head is slightly narrower than the skirt, so there’s less friction between the head and the gun’s bore, while the waist portion doesn’t touch the bore at all.
Traditionally, airgun pellets are made of lead (Pb from Latin plumbum) or lead alloy. In recent times, manufacturers have made airgun pellets from alternative metals, such as alloys of bismuth and tin – or iron, zinc, and tin. Some modern pellets are even made of plastic.
Why are airgun pellets made of lead?
Lead is a soft, heavy metal, and it’s cheap.
Lead is softer than the steel of a gun’s barrel. This is important because it means that friction doesn’t cause abrasion to the inside of the barrel. Being the softer of the two metals, it’s the lead that’s worn by friction. Consequently, brushing lead residue from the gun’s bore is a routine part of airgun maintenance.
The softness of lead comes into play again when the pellet makes impact with the target, which is particularly important for hunting or vermin control. When the airgun pellet makes impact, it crumples, unable to retain its shape. The crumpled head of the pellet creates a larger wound and a quick, humane kill.
Lead’s most common alloy partner in airgun pellets is antimony (Sb from Latin stibium), a metalloid that adds hardness to lead.
The heaviness of lead is also significant. With a density of 11.34g per cm3, a small lead pellet carries a proportionally large amount of momentum. Speed may be top priority when it comes to target shooting, but when you’re shooting live quarry, you need some weight behind your shot. The Crosman Premier domed pellet is an example of a reliable lead airgun pellet.
Copper-coated airgun pellets
Copper (Cu from Latin cuprum) is also quite a soft metal, but it’s harder than lead. A copper-coated pellet engages well with the airgun’s rifled bore, but, being softer than steel, it causes no abrasion to the inside of the barrel. Being harder than lead, copper creates less friction with air, so velocity is maintained.
Lead-free airgun pellets
Bismuth (Bi from Latin bisemutium) is a heavy metal with physical characteristics in common with lead. However, unlike lead, bismuth has a low level of toxicity. Bismuth is commonly alloyed with tin (Sn from Latin stannum).
A lightweight pellet maintains velocity, and consequently keeps a flat trajectory, so for target shooting, a plastic pellet like the Gamo Lethal, which has a copper tip, is ideal for those who are concerned about lead pollution.
For more information about airgun pellets, give us a call on 01263 731 585 or email [email protected].