How to improve your airgun’s accuracy

Perhaps your new rifle’s not as accurate as you’d expected, or maybe your trusty tack-driver’s failing to deliver. Mike Morton runs through a few pointers to help get you back on target

If your rifle’s brand-new you may find it becomes easier to operate – and more accurate – the more it’s used. You can speed up the process by firing into a safe backstop.

Accurate shooting can put food on the table, medals on the mantelpiece or just a massive grin on your face. It’s great when everything comes together – but it can be immensely frustrating when it doesn’t. The excitement of shooting a new gun can quickly diminish if you don’t achieve the results you expect.

And in some ways it’s even more frustrating when a rifle you know is capable of truly accurate shooting starts to behave like a blunderbuss. Luckily things usually go wrong for a reason, and can therefore usually be put right again.

It’s a question of examining the hardware (the rifle, scope, mounts and ammo) and the software (us), then diagnosing the problem and agreeing the right course of action.

What’s the first ingredient of accurate shooting? Honesty. That means being honest about your ability and expectations. A cheap plinking rifle, even in the most skilled hands, won’t be much use for competition shooting. Similarly, a high-end Field Target rig may well turn in some truly awful results until the shooter has learned how to use it.

Being honest about what you and your rifle are capable of will help you focus on what you’re trying to achieve. Expecting a rifle to consistently deliver five-shot groups measuring one pellet’s width at 60 yards is a bit like chasing rainbows.

Action screws may be used to hold the trigger guard in place

Improving airgun accuracy: loose screws

Let’s start the problem-solving process by looking at screws. A loose stock screw can really throw the relationship between point of aim and point of impact for some rifles, while for others it can make surprisingly little difference.

Nevertheless, stock screws are a good place to start looking for trouble. Springers typically have two screws at the forend as well as the belly of the stock or the trigger guard. PCPs may have one or two screws. If the action is loose in the stock, your head/eye alignment with the sight won’t be consistent. Remember: consistency equals accuracy.

A torque wrench or driver isn’t essential, but removes the need for any guesswork. This particular driver is made by Felo and can tighten screws over a range of 1.5 to 3.0 Newton metres

Scope mount screws can also come loose – sometimes even if you’ve used threadlock. An angled scope will induce cant, and that in turn means your pellet will not be intersecting your point of aim at anything other than your set zero distance.

Before you start checking your mounts for any loose screws, make sure the scope is exactly where it should be, and that means perfectly level with your action. You’re not mounting your scope again, just verifying it’s still in exactly the right place. Check the screws clamping the mounts to the rail as well as the rings themselves.

Improving airgun accuracy: check your scope mounts

Ensure you have correct eye relief before tightening your mounts. Check the scope is level with your action to avoid cant. One trick is to align a bubble level on the scope’s elevation turret cap with a second bubble level mounted on the action.

1. It’s hard to get perfect eye relief for every shooting stance. Either go for a happy medium in a number of stances, or set perfect eye relief for the shooting stance you’ll be using most often.
2. Make sure the mounts are tight to the rail – use a torque wrench if you have one. If you choose to use threadlock, use the blue non-permanent type so you can reposition the scope if needs be.
Spirit levels are great for checking the scope and rifle are both level. An alternative is to use a plumb line, but it won’t tell you whether your rifle is level in relation to your crosshairs.
3. If you’re not using a torque driver to secure the upper rings, make sure you use the short end of your Allen key to avoid over-tightening the screw and potentially crushing the scope tube.

Improving airgun accuracy: cleaning

I’ve known plenty of rimfire shooters as well as air rifle shooters over the years who have never cleaned their barrel. It wasn’t because they were lazy, but because they genuinely believed their rifle was fine and the barrel didn’t need cleaning.

They were partially right. Any barrel firing a lead projectile needs to have a thin film of lead deposited on the lands and grooves. This process, known as leading, fills imperfections in the barrel and reduces friction.

While leading is beneficial, the layer will continue to build up as more shots are fired, and after a period of time this will start to impair accuracy. This is one of the main reasons why a rifle that had been shooting well may now be shooting wild. Its barrel needs cleaning and re-leading.

It’s tempting to use the long arm of an Allen key because it feels better in the hand and offers greater torque – but it’s all too easy to apply too much torque to a delicate scope.

How often you clean will depend on the type of barrel, the type of pellet, the velocity and the existing level of leading. Air Arms, for example, suggests cleaning a barrel after every 250 shots.

You should certainly clean your barrel whenever you suspect accuracy is degrading, all other factors remaining equal. Once cleaned, the barrel must be re-leaded, and this can take anywhere between five and 50 shots. I’ve found 20 to be the sweet spot – but, as they say, your mileage may vary.

Improving airgun accuracy: barrel cleaning

It really is necessary to clean a barrel, even a brand-new one, where the bore may have been coated in packing grease and picked up microscopic pieces of swarf.

1. A pull-through, like the one here from Napier, is great for cleaning a barrel either at home, at the range or even in the field.
2. Once you have a clean barrel, it’s necessary to fire a few shots to lead the barrel. Your rifle will probably not deliver very accurate results during this leading-in phase. It may seem a waste, but to speed things up you could just shoot directly into your backstop.
3. When changing pellets it’s tempting to just crack on with the testing, but you’re not really giving each pellet the chance to perform at its best unless you do at least a quick maintenance clean beforehand.

Improving airgun accuracy: picking the right pellet

It’s sometimes easy to get upset with the level of performance a rifle is delivering and blame the gun, but another aspect of shooting which can have a huge effect on accuracy is pellet selection.

There are no hard and fast rules other than to make sure you try several types to see which ones your barrel prefers. Sometimes you’ll get it right first time, and sometimes it can take much longer.

In some cases I’ve struck lucky with the very first pellet tested, whereas others have taken far longer – 11 different pellets being my longest search for perfection. The rifle in question wasn’t bad – far from it. In fact it’s a real tack-driver – provided it’s fed the right pellet.

If your rifle isn’t delivering the performance you think it should, it’s usually for a good reason. A systematic check will eventually find and fix the problem in most cases.

Pellet prep can help – and that means a combination of washing, lubing, head-sizing and weighing – but that’s a process best employed for fine-tuning a pellet you already know works well in your rifle, rather than a means of finding the right one to start with.

Once you have found a good pellet, check the batch number and buy as many tins from the same batch as you can. Pellets do vary from one batch to another.

Something else to consider, particularly with brand-new guns (or second-hand examples that look as if they’ve not seen much use), is to put a fair few shots through the gun before passing judgement.

Some guns – usually springers, but sometimes PCPs as well – really need a period of use to allow everything to bed in. Some rifles with super-tight tolerances also benefit from a little wear.

Depending on the rifle and what shooting, if any, it saw at the factory, this can range from 50 pellets to 500 or more. You should feel the rifle becoming slicker as you shoot it, as well as starting to see better results downrange.

Felt cleaning pellets, if used regularly, are a great way to maintain a near-optimum level of leading

Improving airgun accuracy: everything in moderation

A moderator may very well affect the point of impact if it weighs down the end of the barrel, but it shouldn’t affect accuracy. If you’re using a moderator that isn’t permanently bonded to the gun, check to see whether or not it needs tightening.

If the accuracy is still off – and you’ll notice this straight away when fitting a new moderator – remove the silencer and inspect the inside of the exit hole for streaks of lead, the presence of which indicates at least some of the pellets are clipping.

This means the threads on the barrel and moderator are not concentric to the bore of the moddy. If you have a lathe you may be able to re-cut the thread on the moderator, but the easiest fix is to either stop using it or try another one instead.

Patches with a little Napier Power Pellet Lube or Power Airgun Oil are perfect for cleaning and conditioning the bore. This is as true of a brand new rifle as it is a well-used airgun

Improving airgun accuracy: velocity

Accuracy is born out of consistency, and consistent velocity is a hugely important factor. This is why people spend so much time, in the case of an unregulated pre-charged pneumatic, trying to find the sweet spot on the power curve.

It’s not just PCPs that can suffer from inconsistent velocity. A springer with a broken main spring, or one that’s been over-zealously greased, won’t deliver consistent power.

The only true way to test consistency of velocity is by using a chronograph: either a barrel-mounted instrument, like a Combro cb-625, or a free-standing device, such as a Shooting Chrony F1 or Skan. Readings with a variation of 20 feet per second are no cause for alarm, and a variation of around 10fps or less is fantastic.

If it’s much over 20fps, however, don’t immediately blame the gun. Try shooting sorted pellets or even another brand of pellet. If you try this and your readings are still wayward, your rifle may need a service or even some sort of repair. If you’re using an electronic rifle, make sure the batteries are fully charged.

If your rifle’s still not shooting sweetly by now, don’t strip it down or put it in for a service just yet: there are a few more things to check first. Take a look at the breech seal on your rifle, if it uses one. Is it missing? Is it damaged? If so, then replace it. Some PCP pellet probes use an O-ring, so again if your rifle should have one, is it still there and is it in good condition?

Some multi-shot magazines also use an O-ring to hold the pellets in place before they are inserted into the breech. These can degrade over time, but the most significant potential problem with a magazine is whether or not it indexes properly.

If this fails to happen, a pellet may be damaged as it enters the breech, meaning accuracy could suffer. You can check this by loading each pellet by hand into the breech. You can do this even if your rifle doesn’t come with a single-shot tray: it’s just a bit fiddly.

Improving airgun accuracy: canting the rifle

Even if the scope and gun have been properly lined up to be perpendicular to each other, cant is still a problem if the shooter doesn’t hold the rifle level. Some people will naturally cant their gun, while others get tricked into canting the rifle if they’re shooting over sloping ground.

1. One way to check to see if you’re holding the rifle correctly is to check the orientation of your crosshairs with a perfectly level reference point. Use a spirit level to draw a horizontal line.
2. A bubble level placed on the action or turret cap will soon let you know if you’re canting your gun. It can be an unpleasant surprise to find you’re not holding it as level as you thought.
3. Some rifles, like this Daystate Pulsar, have a bubble level built in to the dovetail scope rail to let you know at a glance whether you’re holding your gun correctly or not.
4. Some manufacturers, such as Sportsmatch, supply bridge or swing-out levels that attach to the upper ring of your scope mount. It’s easy to look at this type of level even when on aim.

Improving airgun accuracy: trigger

A good trigger won’t make an inaccurate rifle suddenly come good, but it can help. A crisp one- or two-stage trigger, breaking at a sensible weight, will inspire confidence – and keep the gun on aim.

If your trigger is excessively heavy, consider lightening it, but only if you know what you’re doing. If not, take it to a competent gunsmith at your local shop or club.

Of course a good trigger is only useful if it’s being controlled properly. Good trigger technique and follow-through are essential to good marksmanship. The antithesis of this is to snatch a shot, then pop your head up to see where the shot went.

A lack of accuracy can be put down to something as simple as a scope that’s shifting in its mounts. Regularly checking the screws will make this problem disappear.

Let’s break this down. Pulling, or squeezing a trigger was once described to me as like drawing a line in the sand with your fingertip. Pretend your trigger finger is tracing a line from top to bottom and the trigger is somewhere in the middle of that imaginary line.

Keep that trigger finger coming back and when it makes contact with the trigger blade continue to draw it backwards, smoothly and consistently.

Following through a shot means maintaining the aim position long after you think the pellet’s left the barrel. If you pop your head up to inspect your handiwork you’re letting yourself down on two counts: you’re not giving your rifle the opportunity to do its job, and you’re not even properly checking your shot. It’s far easier to spot your shot by staying on aim and looking through the scope.

Improving airgun accuracy: it could be you

By now, you should be confident that your rifle is more than up to the task at hand. Which weak link needs isolating next? It may not be easy to admit it, but it could be you.

If you’re a regular shooter who knows what he or she is about, you are probably not to blame. But are you out of practice? Have you had a break from shooting and returned to it recently? Have you suffered some sort of injury? Are you maybe not quite as fit as you once were and your breathing isn’t under proper control?

Any form of accuracy testing should be carried out from as stable a platform as possible. A PCP fitted with sling swivel studs and shot off a bipod is ideal.

These are all things that are easy to discount and ignore, probably because we don’t want to admit them even to ourselves. I had a bad knee injury a few years ago that seriously affected my shooting.

After some intense physio (thank you NHS), I can now run, ride and shoot again, almost as well as I did before. You may like shooting from a certain stance, but if for some reason you are no longer able to do so, you may have to adapt your shooting style.

If nothing has changed and your rife still isn’t performing as well as you expect, try shooting another rifle, assuming you have one to hand, and see whether or not that’s shooting properly too.

Maybe the outdoor range where you’ve been shooting isn’t as wind-free as you thought, and the other rifle is faring no better. It may be a good idea to swap scopes if you have one available, just in case it’s the scope rather than the rifle that’s at fault.

Another option is to let a fellow shooter use your rifle, but they may need to adjust the scope to suit them better before they can truly test it. If they are doing no better than you, and you’ve exhausted all other possibilities, perhaps it’s time to send the rifle back for a replacement or repair.

Hopefully any accuracy problem you found with your rig will have been caused by a specific issue. By working your way through our checklist, that problem should have been solved, and your rifle is good.

More on airgun accuracy 


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