IMPROVING PELLET PERFORMANCE - Always room for improvement

Using air rifles for vermin control sharpens your fieldcraft skills, as ranges are restricted to 30 yards or so, and you get to learn real accuracy and how to stalk in close. They are also very quiet and cheap to shoot due to the price of pellets compared to rimfire ammunition. However, there are still techniques that you can use to improve the performance of your pellets. They are cheap and easy to apply and will help maximise the consistency, accuracy, and power of your air rifle.

Techniques
These procedures are simple, don’t take up much of your time, and the benefits are so worthwhile.
Compared to rimfires, the low velocities achieved by airguns exacerbate any small change to a pellet, and this can make quite a difference to the pellet’s accuracy and trajectory. Therefore, if we can uniform the pellets we use, by weighing them, washing, lubing, and re-sizing them, then why not? Here’s what I use and how it has helped me improve the accuracy of my airguns.

Cleaning
Although it may sound counter-intuitive to wash or put an aqueous mixture on to lead that oxidises, it does help. Tarnished, fouled, oxidised or contaminated pellets will not shoot the same as pristine pellets, so a pre-clean can be beneficial.
If you were to tip a tin of pellets onto a white sheet of paper, you would see quite a lot of swarf and small lead fragments from the manufacturing process. These can cling to the pellets, and if located on the pellet’s head circumference or skirt, where the air seal is in the barrel, they can cause air leaks as well as inconsistent accuracy.
Large swarf is easily segregated but smaller fragments are best gently washed off. Place a small number of pellets, say 100 .22 calibre or 200 .177, into a small freezer bag and add 50ml of warm water and two to three drops of washing-up liquid. Agitate slowly for five minutes and then tip them out onto some absorbent cloth or kitchen towel. Next, allow them to air dry or speed up the process using a hair drier, revealing swarf-free pellets as they should be.

Weight sorting
This procedure is easy to undertake, takes a minimal amount of time, and only requires the use of a cheap set of digital scales. Each pellet type/calibre will have an average weight that’s measured in grains. The idea is to weigh each pellet and reject those that fall outside the limits of the mean weight. If say a .177 pellet weighs 8.6-grains, then a plus or minus weight of 0.2-grains won’t make a lot of difference to velocities or accuracy. You are looking to reject the 0.5-grain or more oddities.
Looking at the Weight Table, you can see that although my Venom Arms springers shoot sublimely, my group sizes did increase slightly when using the pellets with non-identical weights. In reality, at short distances, say 25 yards, you probably won’t notice the difference, but at 30 to 40 yards, it could be the difference between a hit or miss on a rabbit head.

Lubing
I never really liked the idea of putting anything foreign on a pellet, or bullet, but as with my Wildcat cartridge .14, .17, and .20 cal centrefires, some form of bullet coating does help with consistency and to reduce fouling.
Lubing a pellet has two benefits. If you have washed your pellets, it is best to lightly lube them to stop them from oxidising, as oxidation will increase the friction between the pellet and the rifling in the bore. Lubing improves the shot-to-shot velocity consistency and accuracy, and it also reduces fouling in the barrel, prolonging the airgun’s accuracy. Finally, it is supposed to eliminate any point of impact shift.
Again, a very simple solution using a similar method as washing pellets, but this time you must only use a small amount of lubricant. There are many different pellet lubes on the market, and I use Napier and Daystate. The Napier comes as a liquid and a spray, whilst the Daystate is spray only. Two drops of lube are all you need, but because a .177 has a different surface area to a .20, .22 or .25 pellet, you must experiment a little to get it just right. Napier also suggests a few drops added to a tin of pellets and agitate. I like to line my pellets up on a flat surface and spray lightly 360º around the pellet. See Velocity/Energy and Accuracy tables.

Sizing
Sizing pellets can be a very satisfying way to improve accuracy in your air rifle and doesn’t necessarily need a specialised tool, although plenty are available.
What you are trying to achieve is a perfect pellet whose head and skirt dimensions are totally symmetrical and uniform. They should also match the barrel’s dimensions i.e. the groove diameter.
Lead pellets are usually quite soft and deform easily, so re-uniforming each pellet will help achieve consistent velocities and accuracy. Zinc-based lead-free pellets are harder and a little more tricky, but due to their hardness they deform less anyway. So, in reality, you have two benefits from sizing a pellet before use - matching the barrel’s internals and uniforming the bearing surfaces for a better fit.
The easy route is to use pellets that are available in differing head sizes to match your rifle’s barrel, and these are supplied by many of the pellet manufacturers. For example, a standard .177 pellet measures 4.5mm and is often offered in 4.50mm, 4.51mm, and 4.52mm. This way you can try each differing head size for the same style of pellet that best matches your barrel’s characteristics.
The Venom, which is actually not at all pellet fussy, did seem to like the 4.50mm FFT pellet size, as the velocity was highest and hence energy and accuracy were consistently better than the other two sizes. Other guns I have prefer 4.51mm, so worth checking. See Venom HW77 Vantage table.
The other sizing option is to actually size your own pellets to match your barrel. This can be done by using a pellet sizer. Here, a pellet is swaged through the die so as not to deform it but to yield a uniform and true pellet specific to the diameter you want. This way you know that each pellet is identical to the other, and if you miss, it’s you!
This is very handy for .20 cal pellets, where expanding the skirt can be beneficial. This can be done with the Venom/V-Mach .20 die or, if you have an airgun in .25, T. Robb’s .25 cal pellet swager, which will help uniform the pellets, as the skirts are often dented or deformed in this large calibre.
In the Steve Harper Classic custom .25, velocity reduced slightly but accuracy increased, but with the wide range of pellet weights and styles available, it really is a matter of trial and error. See the Swaging Results table.

Conclusion
Some may think this is a little over the top for a casual rabbit hunt, and I agree, but if you like to achieve the best accuracy possible, a little more time and effort can produce good results. These techniques give the shooter more confidence, especially for airgun shooting when you have spent a lot of time stalking in very close, only to miss because of a duff pellet.