Posts Tagged ‘maintenance’
by Tom Gaylord, a.k.a. B.B. Pelletier
Today is the Memorial Day holiday in the U.S. It’s the day we honor those who have given the ultimate sacrifice to defend our nation. Edith and I would like to join the rest of the country in remembering all these heroes from the Revolutionary War down to today.
This report covers:
• Technology advances as time passes.
• Not all guns changed over time.
• What about 88-gram cartridges?
• How does a charged gun suffer?
• How long can a CO2 gun be left charged?
• Can you leave a CO2 gun charged?
I’m writing this report for my good friends at Pyramyd Air. They get questions all the time about this topic, and they wanted me to discuss the whole story. It’s long, so sit back and enjoy it.
Gas gun technology advances as time passes
In this case, the technology refers to both the design and the materials. In the 1940s, Crosman made CO2 guns that were either charged from a separate bulk gas tank or else the bulk tank was attached directly to the airgun. The gas flow in these guns was very direct — from the tank through the valve and out the barrel.
The Crosman 116 bulk-fill gas pistol was based on 1940s technology. Gas flow was simple and direct.
The seals in these guns were an early form of synthetic material that hardened and failed over time. But in recent years, all the vintage seals for these guns have been reproduced in modern synthetics that have a much longer shelf life and even longer operational lives. When a vintage CO2 gun is fixed today, you can expect it to last a very long time. A gun that might have leaked after 20 years of service in the 1950/60s can be resealed today and not leak again for the next 40 years because of the advances in materials.
In the 1960s and after, the design technology changed. The gas flow in these guns was not always as direct as it had been in the earlier guns. Airgun manufacturers were now making lookalike guns, and they were being constrained to put the CO2 cartridge in certain places such as the grip, where the gas might have to flow for some distance to get to the breech. Small metal pipes were used in some gas guns to transport the gas from where the cartridge was pierced to where the gas was needed. These pipes could not stand up to the pressure of a constant charge, and it was best to leave them discharged until you wanted to shoot the gun. This marked the start of gas guns that could not be left charged.
Another change was the invention of the magazine that also contained the gun’s firing valve. All the seals were in that tiny unit on top of what looked like a conventional pistol magazine. In these guns, the small flat end of the CO2 cartridge was pressed tight against what’s known as a face seal by some kind of tensioning mechanism in the bottom of the grip. When the cartridge was pressed flat, the end seal stopped gas from flowing out around the end of the cartridge; and it only flowed straight into the small firing chamber. The valve held this chamber closed until the action of the hammer opened it with force, allowing some of the CO2 gas to escape.
Face seals usually work quite well, but there are some things about them that you have to know. One is their thinness. If they’re twisted while the CO2 cartridge is pressed against them, they can tear. If that happens, they’ll leak. This is a good reason to always use a drop of Crosman Pellgunoil on the tip of each new cartridge before it’s pierced.
Another thing you have to know is the length of the CO2 cartridge. If the cartridge is too short, the flat spot may not press tight enough against the face seal even when the tensioner is adjusted as far as it will go. That lets the gas leak out because the face seal cannot do its job. The solution for this is to try a different brand of CO2 cartridge.
Not all guns changed
As the technology changed, all gas guns did not change to use the latest designs and materials. The cheaper guns did go the way of face seals, gas tubes and lookalike designs; but there were more expensive gas guns costing hundreds of dollars that continued to rely on the older designs from the early years. These employed the very latest in materials in these designs. I’m referring to the gas guns used for formal target shooting. These airguns will hold gas for years without a problem because they are designed to.
What about 88-gram CO2 cartridges?
This question always comes up. While a gun that uses a 12-gram cartridge may shoot 50 or 60 times per cartridge, guns that use the much larger 88-gram cartridges can shoot hundreds of shots before running out of gas.
Should you remove an 88-gram cartridge after your shooting is done? In recent times, Crosman made a special adapter for their 1077 repeater (among other guns) to accept an 88-gram cartridge. That adapter has a valve that allows you to turn off the gas. The cartridge can remain on the gun, but there’s no gas flowing to the valve. I’ve had my 1077 with this adapter charged this way for several years.
The Crosman AirSource adapter shown here allowed the use of 88-gram cartridges. The knurled knob at the bottom of the vertical tube allows the gas to be turned on and off. This gun still has gas after being stored for 3 years!
Not all airguns that use 88-gram cartridges have a valve to turn the gas off. Shooters who use the 88-gram cartridges costing several dollars apiece must consider the shooting they are about to do to determine the probable number of shots that will be fired because some guns may suffer if left pressurized. If you plan on removing a 300-shot cartridge, better to do it after 275 shots have been fired, rather than only 25 shots. That would be like opening a $200 bottle of champaign so a friend could have a sip.
How does a charged airgun suffer?
A couple years ago, I asked Ed Schultz, Crosman’s top engineer, what damage is done when a CO2 gun is left charged. He told me that some of the modern seal materials can take a set if left pressurized too long. This was the first time I’d ever heard that; but since Ed is in charge of making the guns, I have to accept that it’s true.
There’s a second reason why the gun manufacturers don’t want their guns left charged, but they will never mention it: Liability. You see, a CO2 gun can shoot anything that’s in its barrel. It doesn’t have to be BBs or pellets. So children and irresponsible people can load things into a gun and shoot them even if they don’t have a supply of the correct ammunition. For this reason, a charged CO2 gun is a loaded gun.
How long can CO2 guns be left charged?
This is where the question gets personal. There are owners who obey the letter of the instructions and see it necessary to remove the cartridge within 5 minutes of shooting. If they planned on shooting again tomorrow, they would still remove the cartridge today.
Then, there are the more broad-minded owners who believe that they should remove the cartridges only when they think they’ve finished shooting the gun for a longer time. These are the people who will leave a cartridge installed for a week of shooting. I tend to agree with this group. But, sometimes, they forget what they’re doing and the cartridge never comes out.
The manuals are vague on this point, and I wouldn’t expect a firm answer from an airgun company, either. They have to defend themselves in court for whatever irresponsible actions are taken by those who use their products, so they can’t afford to give them any basis for a lawsuit.
I’ve left my modern CO2 guns charged for years, and eventually they all seem to leak down. Some will hold for more than a year, but eventually they all do seem to leak down.
My vintage CO2 guns, on the other hand, are always charged and never leak. They are like PCP guns, in that respect.
Can you leave a CO2 gun charged?
All of this brings us back to the original question — can CO2 guns be left charged? The answer is sometimes “yes” and other times “no.” It depends on the design of the gun in question.
These days, I tell people to follow the instructions in the manual but not to be anal about it. They can leave a gun charged overnight and even for several days; but before it’s put away, if the instructions tell you to remove the cartridge, that’s what you should do.
by Tom Gaylord, a.k.a. B.B. Pelletier
This report addresses:
• What is a pneumatic?
• No. 1 lubrication need.
• A short pneumatic history.
• Which oil to use?
• Other lubrication.
• Wipe down.
This report was written for blog reader Joe, who asked for it specifically; but I know that many of our newer readers also found the information useful. Today, we’ll look at pneumatic guns. There are 3 very different types of pneumatic airguns — precharged, single-stroke and multi-pump — but I think they’re similar enough to cover all of them in the same report.
What is a pneumatic?
Pneumatic airguns store compressed air for one or more shots. Single-strokes get just one shot per fill and so do most multi-pumps, though there are some that do get multiple shots. Precharged pneumatics (we shorten the name to PCP) get many shots per fill.
Big bores, which are always PCPs, get the fewest number of shots per fill, but the smallbores (.177, .20, .22 and .25) get many. How many depends on the output power of the gun and the amount of compressed air that’s available (i.e., the capacity of the air reservoir).
No. 1 lubrication need
The most important reason to lubricate a pneumatic of any kind is to seal the gun. This is similar to gas (CO2) guns; but since pneumatics use air — which is thinner than CO2, their lubrication is extremely important. The seals in the guns are all sized to their jobs. In the case of o-rings, they sit in channels that assist in their sealing role; but without the right lubrication, all would be lost.
A short pneumatic history
Pneumatics are the oldest type of airgun, and their technology has evolved over more than five centuries. The first pneumatic guns used leather seals in all places to seal the reservoir as well as sealing the firing valve.
As time advanced, airgun makers learned how to lap (polish until smooth) valve faces of animal horn that is much better and less porous than leather. These valve faces would be hand-lapped to match the exact surface of the metal (brass or bronze) valve seats to which they were fitted. When the lapping job was finished, these valves would hold air much longer than leather. Leather was still used to seal the junction around the threads of the reservoir, so the guns still leaked down — but the amount of leakage was reduced by a significant amount.
[Note: Airgun designer John Bowkett determined decades ago that precisely machined stainless steel valve faces and valve seats work best of all, providing there's enough lubrication and the machining is correct. The contact surface of this type of valve is extremely fine and narrow; but if it's perfect, this valve will be very controllable. The downside is that valves made this way are still extremely labor intensive.]
Leather seals and horn/brass valves were still being used in big bore PCP airguns up through the 1920s. Smallbore PCPs didn’t come into being until 1980, when Daystate converted one of their tranquilizer dart guns into a .22-caliber sporting rifle they called the Huntsman. Daystate was the first company to build a modern PCP; and when they did, synthetic materials were both available and far better suited for pneumatic valves. At the same time, o-rings in properly cut channels provided the remainder of the sealing solution in place of leather — and the modern PCP was born.
Synthetic seals are less porous than animal horn and last far longer. They’re not as hard as stainless steel, so the mating surfaces of the valve do not have to be machined as precisely (they have a little give to accommodate slight imperfections in the valve seats). Synthetics make the modern PCP possible. And lubrication is what keeps PCPs sealed almost forever.
Leather seals in other pneumatics
Leather has been used for the peripheral seals in multi-pump pneumatics up to as recently as the 1950s. Just like the leather seals of old, the problem has always been how to keep the leather seals lubricated so they remain soft, pliable and doing their job. Oil was used originally in these airguns in the late 1890s. But times change and today we have better lubricants. Petroleum jelly will stay on the job many times longer than straight oil, so even the leather seals in your vintage multi-pumps can be lubricated for a long time.
Which oil to use?
That brings us to the big question of the day: Which oil to use? In this instance, there isn’t just one answer. For PCPs, the right oil needs to have a very high flashpoint so it isn’t prone to explode when subjected to high pressure.
I know of two instances in which petroleum-based oil or grease has caused an explosion in a PCP. One was a vintage PCP reservoir that was pressurized to around 800 psi. The interior walls of the reservoir were coated with grease to trap any dirt particles that might get in during filling. This is a common practice with such airguns; but this time the person who greased the reservoir used petroleum grease instead of organic-based (animal) grease. The reservoir blew apart at the soldered seam! Fortunately, no one was hurt.
The other instance was one I got from a news story, and the person involved was, unfortunately, killed when his modern PCP reservoir exploded. The article said he had apparently introduced regular household oil into the reservoir.
On the other hand, I’ve safely oiled PCP tanks hundreds of times with a couple drops of Silicone Chamber Oil through the air intake port. I put several drops into the fill port before the gun is filled. When the air blows in, the oil is atomized and gets on all the sealing surfaces inside the reservoir and valves.
The oil to use in a PCP is silicone chamber oil. For single-strokes and multi-pumps, the answer is different. For either of these types of pneumatics I use Crosman Pellgunoil. Neither of these types of pneumatics are pressurized nearly as high as a PCP, and Pellgunoil always does the trick.
Can other oils be used instead of Pellgunoil? Certainly. I’ve used Gamo Air Gun Oil in my single-strokes and multi-pumps for many years. I use it exactly as I do Pellgunoil for single-strokes and multi-pumps, but I do not use it in any PCP guns.
The thing about multi-pumps and single strokes is to keep their pump cups sealed and working well. These are the flexible pump heads that force air into the guns, either one time or several. They tend to get hard over time and lose their ability to seal, but keeping them oiled and in use frequently will prolong their service lives. Not using a pneumatic airgun is what really hurts it.
For normal lubrication of moving parts, both Pellgunoil and Gamo Air Gun oil work fine. So do most gun oils, like Remoil. What you do not want to use is silicone chamber oil for this purpose because it doesn’t have enough surface tension to lubricate properly. Your parts will rub against each other and wear.
As always you can use the lubricating oils to wipe down your gun’s metal and wooden parts, but Ballistol neutralizes acidic fingerprints and lasts on the surface of metal far longer than plain oil. So, it gets my recommendation for this job. It also gets the nod for the insides of all airgun barrels.
Airgun lubrication is important, for the reasons mentioned in this 5-part report. Sealing is the biggest role lubrication performs, in all cases. We’ve looked at some very specific examples of products that should be used for the reasons stated. If you decide to substitute, you do so at your own risk.
by Tom Gaylord, a.k.a. B.B. Pelletier
This report addresses:
• Molecules versus atoms
• Crosman Pellgunoil
• Can’t over-oil with Pellgunoil
• “Fixing” leaking guns with Pellgunoil
• Transmission stop leak oil
• Oiling moving parts
Let’s look at lubricating gas guns — and by “gas,” I mean CO2. What I’m about to say will also work on airsoft guns that operate on green and red gas, because both those gasses work similar to CO2; but there are no pellet or steel BB guns that run on any gas except CO2 (excluding air).
CO2 is a molecule — not an atom!
Many folks thought that high school science class was a waste, but in the curriculum there were things that matter to airgunners. How levers work is one of the most important things, and yet I still see youngsters grabbing breakbarrel rifles five inches back from the muzzle — as though the length of a lever has no significance! The fact that CO2 is a compound made of molecules is also important.
Atoms are very small. When they’re inside a pressure vessel (air is made of several elements that are atoms), they try to escape through the smallest holes imaginable — sometimes through pinholes in the casting of the metal. Molecules are combinations of atoms that are much larger than atoms, by definition. They also try to escape, but they need larger holes to get through. This fact is what saves the CO2 airgunner, and it’s also why CO2 guns can be made with larger tolerances. That makes them cheaper to build.
Crosman Pellgunoil is our friend
When I started seriously shooting airguns in the early 1990s, nobody talked about Crosman Pellgunoil. I didn’t even know if it did anything. Then, I met Rick Willnecker, the man who runs Precision Pellet — one of the top repair stations for vintage CO2 and pneumatic airguns. Rick always had a jumbo bottle of Pellgunoil on his workbench, and he applied it liberally to valves, seals and o-rings whenever he assembled a CO2 gun. He told me that I should always put a drop of Pellgunoil on the tip of every new CO2 cartridge before it was pierced.
You cannot over-oil with Pellgunoil
I asked Rick how much oil was too much. He said it is impossible to over-oil a CO2 gun with Pellgunoil. Apply it liberally. What doesn’t stay inside the gun gets blown out the muzzle. This was all news to me. I’d grown up with the bottlecap CO2 cartridges of the 1950s that leaked before you even put them in your airgun, and I thought CO2 was a gas that was totally unreliable. Rick’s revelation turned this around. I discovered CO2 is a very reliable gas if you use Pellgunoil.
In the 1950s and ’60s, Crosman was capping their CO2 Powerlets with bottlecaps that leaked a lot.
But the discoveries didn’t stop there. Soon after learning about the benefits of Pellgunoil, I bought a Crosman model 111 target pistol at a flea market for $35. It was in the original box and came with the original 10-oz. CO2 tank that Crosman sold with the gun back in the early 1950s. I bought this gun thinking it would have to be resealed. It’s seller told me it had laid in a closet for a minimum of 20 years before she brought it to this flea market, so how in the world could it possibly have any gas left in it?
This .22-caliber Crosman 116 bulk-fill CO2 pistol and tank were sold up until the model 150 came out in 1956.
Well, that gun was still charged! What is even more important was the 10-oz. CO2 tank that came with it was also mostly full, so I was able to connect it to the pistol and charge it many times — for another 50 shots each time. Each time I charged the pistol, I applied more Pellgunoil, and that old pistol kept right on functioning for almost 2 years. When the seals finally did need to be renewed, I took the gun to Rick Willnecker, and he got me started in bulk-filling CO2 guns. I bought my first 20-lb. CO2 tank and the adapter to connect it to the 10-oz. Crosman tank, and I was off to the races. Since that time, I have owned five 20-lb. CO2 tanks and have been filling my own bulk tanks at home for more than 15 years. Where a CO2 cartridge costs about 50 cents, I pay about 5 cents for the same amount of gas!
But it didn’t end there, either. I discovered on my own that by using copious amounts of Pellgunoil, I could get non-functioning CO2 guns to work again. That’s when I started buying up old Crosman gas guns that were leakers and “rejuvenating” them with Pellgunoil. I still own a Crosman 180 rifle that I bought for $20. It has been holding gas for about 20 years so far!
Transmission stop leak oil
Dennis Quackenbush taught me this trick. He said he “fixed” a leaking Crosman 112 bulk-fill pistol with transmission stop leak oil — the stuff you get at the auto parts store. I had a Crosman 116 bulk-fill pistol that was a fast leaker, so I thought I would give it a try. I put several drops of this oil in the fill port connection of the pistol and filled it with CO2. That was about 2-1/2 years ago and that gun is still holding gas today!
Transmission stop leak oil (this is just one brand…there are several others) will swell and make supple the seals inside an older CO2 gun.
Several people wrote comments telling me that this oil would turn the seals in my airgun to mush and it would be an even bigger leaker than before; but as I said, 30 months have passed and that gun is still holding gas. So is Dennis’ gun. This stuff seems to work.
Oiling the moving parts of the gun
You can oil the moving parts of a gas gun with any good brand of gun oil, and I even use household oil (yes, 3-in-One brand) on mine. If you want to buy a good oil from Pyramyd Air, I have used Gamo Air Gun Oil for many years for this purpose. All you’re doing is providing simple lubrication, and oil is correct for that.
Finally, you can wipe down the gun — wood, metal and plastic — with Ballistol. Ballistol removes rust, protects against fingerprint acids, lubricates and generally is the single best lubricant for an airgun or firearm.
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 Ballistol. Nothing too special, and it does the job right. I also use WD-40 for CO2 guns — as a preventive to get rid of water.
A word of caution about oils. Make sure they don’t get into any place where there’s compression, especially when it comes to sprays. In the case of springers, they can cause intense dieseling — or even detonation — and broken seals and springs. In the case of single-strokes or multi-pumps, you can get yourself a very nice tiny working diesel engine — and some purple-black blood-blistered fingers for your troubles.
Do not use silicone oils. Just don’t — they’re simply not for cleaning metal. [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!
by Tom Gaylord, a.k.a. B.B. Pelletier
Today, I’m starting a long series on lubricating airguns. Blog reader Joe asked for this; but as I was researching the subject, I stumbled across another request that came in through the customer reviews on the Pyramyd Air website:
“I wish that RWS or Pyramydair would explain the process and frequency of oiling these RWS rifles in particular the RWS mod 48. Everyone I talk with says the RWS owners manual is outdated and that with the new seals they use does not need to be lubed maybe for years….I purchase the RWS chamber and cylinder oil at a cost of almost $30.00 and now am told I probably will never need it? This topic should be cleared up once and for all by the manufacturer.”
Perhaps this customer is referring to RWS Chamber Lube and RWS Spring Cylinder Oil as the two products he purchased. And they do add up to $28 before shipping. Are they necessary? Should he have bought them? That’s the question I’ll start answering today.
This subject is so vast and complex that I cannot address it in a single report. In today’s report, I’m only going to look at lubricating the piston seal. That constitutes about half of the lubrication requirements for many airguns, in my opinion. In the next installment, I’ll address all other spring gun lubrication, including the mainspring and piston.
Leather piston seals
In a spring gun, the piston seal is what compresses the air when the gun fires. As the piston goes forward, the seal keeps the air in front of the piston, where it gets compressed because the only escape is blocked by the pellet sitting in the breech. If the gun’s working properly, all other avenues for the compressed air to escape have been blocked.
In the past, pistons were sealed with a leather pad or cup. Leather is an ideal material for this job. It’s rugged, lasts a long time and will conform to the shape of the compression chamber after a few shots — much like a leather shoe that eventually fits your foot perfectly.
This cup-shaped leather piston seal is for a Chinese spring rifle.
To do its job, a leather seal has to stay soft and pliable, and oil is the best thing for this. As the spring gun operates, a little of the oil is consumed with each shot, so a leather seal needs to be oiled frequently to stay soft. How frequently? In some older guns, I’ve found that oiling every few weeks is necessary if they’re shot a lot. Certainly, all guns with leather seals need a couple drops of oil at least once each month if they’re to be shot. You can leave a gun with leather seals unoiled for years if you don’t shoot it; but before you start shooting it again, that seal needs to be oiled. When I start shooting an older gun that I know has leather seals (I use references for finding out things like this), I put about 10 drops of oil through the air transfer port and let it soak into the seal for at least an hour, although a half day is even better.
What oil to use?
The type of oil you use depends on the velocity of the gun. Guns that shoot less than 600 f.p.s. in both .177 and .22 caliber will be oiled with regular household oil. Any petroleum-based lubrication oil will do. Yes, gun oil will also work. For guns that shoot faster than 600 f.p.s., I use silicone chamber oil, like the product listed above. The spring cylinder oil is not for chambers and should not be used on the piston seals of these guns.
Starting in the 1950s, manufacturers began experimenting with piston seals made from synthetics. Some of them, like the ones used by Anschütz and Falke, worked well and lasted for many decades. But others, such as the seals used by Walther on all their airguns and the seals that Feinwerkbau used on the 121 and 124/127 sporting rifles, were made from a material that dry-rotted within about 20 years. If they were oiled by anything, they failed even faster. These seals started out as a light beige color, but as they absorbed oxygen and oil, it turned them dark yellow and brown until they began to break apart in waxy chunks.
Diana was one of the last companies to switch from leather to synthetic, and they had the benefit of watching the others. They were still using leather seals in their powerful model 45 rifle in the late 1970s, at a time when that airgun had broken the 800 f.p.s. “barrier.” When they started making synthetic piston seals, they used a blue-colored material that was tough and long-lasting. It’s interesting to note that the others adopted similar piston seal material when they finally realized their seals were perishing in use.
The blue Diana parachute seal is so rugged that hobbyists use it for many other airguns. It needs very little oil!
These 2 FWB 124 seals are made from modern synthetic material, yet they look like the original ones. The one on the right has been inside a rifle for a few thousand shots. It looks bad but is still in great shape and will last for many decades.
Don’t fixate on the color blue for piston seals! These synthetics can be colored any way and still be fine. I have modern FWB 124 seals that look similar to the old seals in color, yet they’ll last indefinitely. It’s the material, not the color.
Which oil to use?
With synthetic seals, I always use silicone chamber oil. That’s SILICONE CHAMBER OIL — not brake fluid, silicone spray lubricant or any other concoction. Chamber oil is for piston seals. It does not lubricate metal parts because the viscosity is too low. It’ll ruin metal parts if you use it that way. On the other hand, nobody knows what will happen to a gun that’s lubed with anything other than SILICONE CHAMBER OIL.
Diana recommends using two drops of chamber oil on the piston seal every 1,000 shots, and one drop on the breech seal at the same time. That’s it. To answer the person who asked if he needs the chamber oil, the answer is yes. But one small bottle will last a long time. I’ve observed that most Diana airguns can get by with even less oiling than what’s recommended. One diagnostic for when a gun need its seal oiled is when the seal honks like a goose as the gun is cocked.
Silicone chamber oil has a high flashpoint. Since the air in a spring-piston gun reaches about 2,000˚F with every shot, this is important. This heat is adiabatic — it doesn’t heat the gun because the interval is too brief.
Overlubing vs. underlubing
It’s almost impossible to overlube a leather piston seal. And it does not harm the seal if you do.
On the other hand, overlubing a synthetic seal can start the gun detonating. Not dieseling — most spring guns diesel. When you smell burning oil, your gun’s dieseling. Dieseling is just a few oil droplets vaporizing with each shot. It’s perfectly normal in a spring gun.
Detonation is when a lot of droplets vaporize and cause an explosion. That will damage your piston seal if it’s allowed to continue for a long time. It can also break your mainspring.
So, dieseling is okay, but detonations are bad. And overoiling synthetic seals causes detonations.
Do you see why I had to cover just the piston seals today?
by Tom Gaylord, a.k.a. B.B. Pelletier
I’m still in Ft. Smith, Arkansas, as I write this, so please excuse the brevity of the report. A while ago, I wrote down this idea as a possible report topic. Those who haven’t yet come over to PCPs often wonder how reliable they are, and those who already have the guns sometimes encounter things that are common problems but new to them. Let’s talk about that today.
WARNING: The procedures I am about to describe are for those who know what they are doing. In every case, there are proper safety steps to be taken so accidents don’t happen. I cannot possibly describe all of those steps, so the following procedures are presented only for your education — not to train you as an airgunsmith. Safety with pressurized air and airguns should always be the No. 1 concern.
I can’t fill this airgun!
Boy, have I ever heard this one! It can come to you in a variety of ways, such as, “This airgun is broken — how do I return it?” I used to get at least one of those calls every month while I was the technical director at AirForce Airguns. The first few times I heard it, I was worried; but I got so used to hearing it that I would start telling them the cure before the problem had been fully stated.
The guy would tell me that he couldn’t fill his old-style Condor tank. I asked him how he was trying to fill it — from a scuba tank or with a hand pump — and a lot of times that made the guy mad. He wanted to know why that mattered because he should be able to fill the gun from a scuba tank or from a hand pump. Right? When this call came in, I knew he was filling with a hand pump, and I also knew he was trying to fill an empty tank.
The answer to “can it be done” is both yes and no. Yes, you can fill this kind of tank from a hand pump if there’s already some air inside it, and no, you can’t fill the tank if you start with it empty. That would really anger some people until I explained that the air inlet valve on an old-style Condor tank is also the exhaust valve. It’s a door that swings both ways. If there’s no air inside the tank, the valve will not recognize the small puff of air from a hand pump and will escape, again.
The valve will not close because it also uses internal air pressure to help it close tight. If you fill the tank from a scuba tank, the incoming air is under so much pressure that it will fill the tank quickly, and the internal air pressure will help close the valve when the filling stops.
A hand pump cannot fill some pneumatic airguns (not just Condors) unless they already have some air pressure inside to hold the inlet valve closed. We would ship tanks out with what we called a maintenance air charge in them — just enough pressure to hold the valve shut. But if the guy received the gun and then proceeded to shoot all that air out, as some of them did, they then had a gun that could only be filled from a scuba tank. It’s not funny when it happens to you.
This phenomenon is not just confined to AirForce guns, either. Almost all of the powerful Korean airguns work in a similar way. But the Korean guns can accept a charge by simply cocking the bolt — sometimes. In that case, taking the pressure of the bolt off the valve allows it to close and seal completely.
The newer style of Condor (as well as all other AirForce sporting PCP rifles) has a Spin-Loc tank with a separate inlet valve and firing valve. I’m not certain, but I believe this has solved the problem I just discussed. If I had a tank and pump here with me, I would check it right now. I’ll look into it when I get home.
Now you know two things about PCP “leaks” that are both very common problems and often misunderstood. First, they aren’t really leaks. They’re part of the gun’s design. Second, some guns must first be cocked to be filled.
Before you go all — “They shouldn’t design them that way!” on me, remember, the SR-71 Blackbird reconnaissance plane leaks fuel until it flies fast enough to heat and expand the airplane’s skin. Only then do all the leaks stop. Sometimes, a product can have a quirk that isn’t a flaw — it’s just the way it works. The Sheridan Supergrade rifle is one that cannot be pumped up unless the bolt is cocked first.
Use a hammer!
I probably shouldn’t tell you guys this next one; because when some of you get a hammer in your hands, every problem looks like a nail. But in the world of pneumatics, there are times when a big rubber mallet is exactly the right tool to use. When is that time? When a pneumatic that has been performing well all along suddenly develops a fast leak. It’s probably due to a piece of dirt that’s gotten onto a soft seal and is allowing air to pass through. To get it off the seal, it sometimes works to tap the end of the valve with a soft hammer. It opens the valve, and the blast of air will probably blow the dirt past the seal.
When I built valves at AirForce, I tested each by pressurizing them in a fixture and tapping the valve stem with a rubber hammer. I had racks of 100 valves at a time, and I went through and did this to each one in turn. That process seated the valve and created a small ring of contact between the synthetic valve and its seat. Sometimes, the valve needed to be hit several times to seat it properly, but it always worked. And it also worked if a valve had a small piece of dirt anywhere in the seals.
When customers would call with a gun that leaked and I determined the leak was a fast one that had popped up all of a sudden, I told them to try this procedure before sending the tank back for repairs. It fixed probably over 75 percent of all such leaks.
But this isn’t magic. If your gun has been a slow leaker the whole time you’ve owned it, this isn’t going to change a thing. It’s just for those all-of-a-sudden leaks that crop up sometimes. It will work for all guns, but most of them don’t allow direct access to the valve head like the AirForce tanks do. For those, you can do the next best thing — dry-fire the gun several times. That usually fixes the problem unless you’re timid about it. I sometimes had to get a timid owner to dry-fire his gun by telling him to fill it full and then dry-fire it 20 times in rapid succession. All that was doing is getting him to dry-fire the gun repeatedly without pausing to see if it was fixed yet. When there’s a piece of grit on a seal, it takes a lot of air flowing past to dislodge it, and a couple tries are often not enough. Twenty shots is probably overkill in all situations, but it saved me time from having to explain in detail just what the guy was doing — as I have now done for you!
You now know a genuine airgunsmith procedure! It isn’t as fascinating as it sounded, is it?
Okay, let’s go back to 1960, when cars had points and copper spark plug wires with (sometimes) poor insulation. Mechanics had a genuine stethoscope in their toolboxes. Or if they were shade-tree mechanics, like me, they had a 4-foot length of small rubber hose. We would put one end of the tube to our ear (the ear that worked best) and move the other end around the engine compartment while the motor was idling. You could quickly zero in on an arcing sparkplug wire or an exhaust manifold leak. It also works for precharged airguns!
You don’t need a hose because the barrel is the pipe that transmits the sound. Cock the gun but don’t load it. The sound you’re listening for is an air leak at the exhaust valve. But here’s an important safety tip — never put your ear directly over the muzzle and never do this if the gun is loaded! Listen from the side of the muzzle; so if the gun were to fire, the air would blast past your ear instead of into it! You can use a piece of paper to direct the sound, if needed. That keeps you safe and still lets you hear the smallest sounds.
I’ve found a number of valve leaks this way. This is just a diagnostic tool — it doesn’t do anything to fix the valve.
If your ears aren’t that good, or if you just don’t want to do it this way, you can also put a few drops of soapy water down the muzzle of a cocked gun. Bubble-blowing solution that you can buy at a dollar store works perfectly for this! If any air is escaping the valve, there will be bubbles at the muzzle. I always had a small bottle of bubble-blowing solution next to me when I worked on guns at AirForce. Of course, you have to clean the barrel and wipe it with an oily patch after doing this.
These little procedures have proven very valuable over the course of time. If the situation is right, they’ll fix the problem more often than not. While they seem simple to the point of being somewhat ridiculous, they do work.