by Tom Gaylord, a.k.a. B.B. Pelletier
Today’s report is a guest blog from reader duskwight. It’s about how and why to clean airguns. It’s longer than our usual blog posts and filled with lots of info you’ll need.
If you’d like to write a guest post for this blog, please email me.
What we put into our airguns — and what it puts into their barrels
Everybody knows we shoot lead. So-called “ballistic alloys” are a poor substitute for it, so let’s all pretend that we shoot lead.
Lead is a soft, malleable metal — so malleable that a pellet’s skirt blows out when hit by compressed air and presses into rifling. It’s also so soft that during the Middle Ages it was used for pencils, as it leaves dark lines on paper or parchment or human hair! Yes, people made lead combs to dye their beards and hair while combing them — they didn’t live that long back then, anyway. Remember that, though, and wash your hands thoroughly, especially when you’re covered with a lead and oil cocktail, because it’s readily absorbed.
So, lead leaves traces of itself on things. Sometimes, it leaves even more than traces — as in whole deposits of lead. Just imagine a lead pencil drawing a line all along the inside of your barrel, and you’ll get the picture. Freshly exposed lead is so shiny and bright — it’s also quite sticky and shaves off your pellets to form thin (foil-like) deposits inside your barrel. It looks like tiny shavings or scales, pressed and stuck onto the metal.
Of course, that’s not all. Some pellet makers use graphite dust to prevent pellets from sticking to each other inside their tins. Some use different types of grease (e.g., tiny amount of petroleum jelly dissolved in a good amount of solvent to form a thin coat after a short wash) to prevent them from oxidizing while being stored. Some use both. There’s all sorts of lead dust and tiny shavings of lead coming off pellets. The better the quality of your pellets, the less dirt they bring with them. But they’re all dirty. And compressed air, especially in a magnum springer, carries tiny amounts of grease, fat and oil to combust — creating different sorts of tar and carbon for the barrel.
And there’s other bad stuff inside, but only for CO2 guys. Carbon dioxide cools as it expands rapidly in the barrel, and it condenses out some tiny amount of water from the air. It can also contain some water of its own. Carbon dioxide plus water is unstable carbonic acid H2CO3 (fizz water anyone?). It is a rather weak acid; however, it’s still an acid.
What it means for your rifle or pistol
The rule is simple. You shoot, and you foul your barrel. It’s inevitable, just like every breath you take brings some very strong oxidants into your lungs.
Then comes the next rule — dirty barrels tend to make you miss. This is simple, too. Compare it to driving on a highway or autobahn (in case you use German-made barrels) — that’s a clean barrel — versus country roads beaten up by tractors and ill repairs — that’s a dirty barrel. Deposits in your barrel make your pellet’s ride unstable. What’s worse is when the deposits collect near or on the crown. They force the pellet to leave your barrel with an unequal force on all sides, making it prone to tumbling, less stable and imprecise. They can also deform or mar the surface of your pellet, affecting aerodynamics and hurting accuracy.
Match-grade barrels with polished grooves collect less lead. Poorly manufactured barrels with “cheese-grater” surfaces scrape off more. Polygonal or segmental rifling tends to catch and hold less lead than classic Ballard rifling because of fewer cutting edges, lower lands and less spaces for lead to stick. The smoother your airgun shoots — the less brute force is applied to the pellet, the less fouling is left. Springer super magnums seem to be the champions of brute force (which makes them lose accuracy soonest). Choked barrels tend to catch more lead in the choke; barrels that are straight cylinders tend to get dirty more uniformly.
The main thing to learn from all this is that there’s no certain equation between the number of shots and aforementioned effects. Every barrel and every rifle has its own character and own number of shots to get dirty. For example, my Feinwerkbau C62 Luft needs 2,500 shots to get dirty, while my modified Gamo CFX with Lothar Walther barrel gets 500-520 shots before it needs to be cleaned. My Feinwerkbau 300S likes to be cleaned every 1200 shots (although I suspect that’s me being paranoid, not exactly the rifle’s barrel). An IZH 60 I have seems to have no limit at all. That’s what you get with segmental rifling and low power. However, the same modified Gamo CFX with the same Lothar Walther barrel (except for the wood) I made for my friend wants to be cleaned after every 550-600 shots. And another buddy’s FWB C62 wants cleaning after 2,000 shots.
Keep in mind that I use just 4 different types of pellets for my fleet – all of them are .177. Multiply that by the number of rifles — each of them can (and probably will) like its own sort — H&N, JSB, CP, Eun Jin, etc. — and calibers — .177, .20, .22, .25, .30. Don’t go crazy doing this. Learn your guns, get intimate with them and know their habits and likes.
Oh, you’ll know when the barrel finally gets dirty! Your perfectly tightened, perfectly tuned and sighted airgun starts to spit like a mad camel! Pellets start to fly chaotically, hitting where you don’t want them.
If you’re lucky (which means you have a “predictable” barrel), the accuracy fall-off will start sharply — just 5 or 10 shots, and it’s shooting horribly. If you’re not so lucky, it will drag along for 50 or more shots, with some being better and others worse. Up and down you’ll go — getting tighter then trashier groups. Anyway, it will happen. That tells you things got dirty, and it’s time to clean.
Some shooters clean after every session. Some clean according to a regular preventive schedule — when the shot count comes to the predetermined number of shots. And others just wait until the inaccuracy gets obvious. I’m somewhere between the second and third type. I don’t like to disturb barrels too often.
What we clean
Airgun barrels are made of steel or brass. Steel is tougher, yet it’s not the same kind that’s used for powder-burners. It’s softer and of a simpler composition, not chromed and so on. Brass is even softer and less durable, but it has a lower friction coefficient with lead and tends to collect less lead than a steel barrel.
A good clean airgun barrel looks like mirror — shiny and amplifying light. Dirty barrels look dusty, and their insides look smoky and blackened. Some even drop lead dust when shaken.
What to use for cleaning — and what not to
The rule in this case sounds like that – nothing can enter the barrel that’s harder or as hard as the barrel metal. The worst thing that can happen to your barrel is a damaged crown. That’s a death sentence for your barrel’s accuracy.
So, steel rods and steel brushes go directly to trash for both steel and brass barrels. [Note from B.B.: Some gunsmiths recommend a one-piece polished steel cleaning rod for cleaning steel barrels. They claim it doesn’t harm the barrel because it’s smooth.]
Steel rods coated with plastic are good. Brass rods are good for steel, but not for brass. Wooden rods — if you can find one in .177 caliber — are ok. Plastic rods are ok too. Different kinds of cloth “snakes” are also ok.
Brushes are usually made of one of three materials — brass, plastic or cotton (they call the cotton ones mops). Brass on brass doesn’t play; save it for your steel barrels. The rest are OK.
Patch-holding tip — get a brass one for steel barrels and aluminum alloy for brass barrels.
Felt patches — I use them for quick cleaning or refreshing the barrel on the range. I load 2 dry with 1 wet between them, and a pellet behind all of it to give a springer something to push against and save the optics — or nothing in case of a PCP. But that’s not proper cleaning, no matter what the ads say.
Thin cotton cloth — clean old t-shirt is quite ok; special wads are too posh for true tough guys (any dry cotton is OK).
As for oil — I prefer [Note from B.B.: Silicone oil is used to seal pistons. It doesn’t lubricate, it seals.]
Ah, and one more thing. You need a tiny and very bright single, white LED flashlight to check the barrel’s condition. This is a useful amateur gunsmith tool.
Getting things done
Brass barrels are exotic these days. If you have one — use a plastic brush.
Steady your rifle, preferably in the horizontal mode. The less bend you’ll give to your rod, the better.
Close all the glass optics with covers. Should I remind you that your rifle must be uncocked, unloaded, de-pressurized and checked twice for maximum safety?
It’s best to clean the barrel from breech to muzzle. Well, I think that’s a bit of a superstition. With good equipment and steady hands you can clean it in the reverse direction — and you often have to. Especially, since some guns do not give you easy access to the rifle’s breech.
Let’s say we have a VERY dirty steel barrel on our hands. Don’t laugh — it happens! Put a brass brush on your rod. For brass barrels (they’re hard to get this dirty), use only plastic brushes. Spray it with Ballistol to wet the brush.
Drag your brass brush along the barrel 5-10 times. Not fast, not slow — just calm and steady. The brass brush will scratch all the big lead deposits off barrel walls and won’t hurt your steel barrel.
WATCH OUT FOR RUBBER RINGS AND OTHER DAMAGEABLE STUFF INSIDE THE BARREL AND PAST THE BREECH.
Now, wait for a couple minutes. Then, screw your patch-holding tip onto the rod. Get some cotton onto it or use a patch of cotton cloth. It must sit tight inside the barrel. Spray some Ballistol to make it wet. Run it 5-10 times through the barrel in both directions. Take it out and say, “Eek!” It should be black with some tiny, shiny flakes of lead.
Change the cloth or cotton and repeat 5-10 times. Aaah…now it comes out dark grey. Change patches again. This one comes out light grey. Change and clean until it comes out white. This alone works fine for regular cleaning if your barrel doesn’t tend to get extremely dirty.
Congratulations, you just got yourself a nice, clean barrel. However, you must finish the job.
Use a loosely woven dry cloth or cotton on your patch-holding tip or use a cotton brush to dry the barrel. Don’t be afraid. One run will not leave the barrel dry, it will leave just the right amount of oil that you need in metal pores and on its surface. You’ve heard the expression, “A light coat of oil?” That doesn’t refer to a wardrobe choice.
Then, if you like — shoot 3-5 pellets into a pellet trap to season the barrel. This will give you a thin film of lead that gives the barrel its standard accuracy and voila! Your barrel is ready to punch hundreds more precise and clean holes in paper.
For polished match barrels that are not very dirty, I use the method of some Olympic airgun shooters. It puts minimal (well, they are prone to overplaying safe) influence on the barrel and makes things extremely right and tender.
Get a fishing line – very good stuff to clean match barrels. I prefer 0.40mm Japanese line. Get 5-6 feet, fold in two, knot, pass through the barrel, loop outside the breech, knot outside the muzzle. Put a narrow strip of cloth into the loop (in my case — 6″ long, 1/5″ wide, 2 loops for .177), soak it with Ballistol, put the rest of the cloth over your fingers (as fishing line DOES cut!) and just pull steadily and slow. This will drag the cloth through the barrel and clean it. Repeat with wet cloths until it comes out white. Finish with one dry patch. Perfectly clean!
There’s another kind of problem with CO2 guns that I mentioned before — water and carbon acid. To maximize your CO2 gun’s service life (don’t consider it to be just a plinker — FWB and Walther made some Olympic CO2 match rifles, and the Hämmerli 850 AirMagnum is a serious piece even by today’s standards), depressurize it and apply some WD-40 into the barrel with a cotton brush or patch-holding tip and cotton cloth after every session. This will get the water out of the pores and preserve it from rust. The same goes for shooting PCPs and springers in misty or high-humidity outdoor conditions.
And a finishing touch — gently rub your rifles steel parts with a soft cloth, slightly wet with oil. Congratulations — you’re done!