Posts Tagged ‘maintenance’
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
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.
by Tom Gaylord, a.k.a. B.B. Pelletier
This blog is for those who are new to shooting and to airguns. Sometimes, we have to address the basics, and that’s what I’m going to do today. I’m inviting the veteran shooters to chime in with their own ideas of what the new airgunner should avoid.
For reasons I cannot fathom, new shooters think they need to clean their airguns even more than firearms are cleaned. I know people who never clean their .22 rimfires until they start to malfunction, yet these same people don’t hesitate to take a bore brush to the barrel of their favorite air rifle every chance they get. It isn’t necessary to clean an airgun barrel that often, and it actually exposes it to possible damage from the cleaning process gone wrong.
Why do we clean a gun?
Historically, guns used what we now call black powder, whose residue both attracts moisture and then turns it into sulphuric acid. It begins to do this in less than 24 hours following shooting, so cleaning was/is essential if the bore was to be preserved. Later, when smokeless powders were developed, the early primers that ignited them contained compounds that were just as corrosive to the bore as black powder residue. A great many .22 rimfire rifles have lost all their rifling from the combined activities of this primer-based corrosion, coupled with over-zealous cleaning.
More recently, shooters have discovered that the jacketed bullets of centerfire cartridges will quickly foul barrels with metal deposits. While this doesn’t corrode the metal, it does fill the rifling grooves with jacket metal until all hope of accuracy is lost. So, the metal fouling has to be removed with a combination of chemical and mechanical action.
The modern .22 rimfire, in sharp contrast, uses clean-burning powder, clean priming and shoots clean lead bullets at low velocities. Nothing in its makeup or operation requires frequent cleaning. Those who shoot .22s can get away with not cleaning their guns for many hundreds and even thousands of rounds. Eventually, there will be a buildup of powder fouling even in these clean guns, but the contrast with centerfire guns is vivid.
Finally, there are the airguns. They neither burn powder nor use primers, so there’s no residue. They shoot at low velocities (compared to many firearms) and use clean lead pellets, so there’s little metal fouling. Only with some of the more powerful airguns do the velocities get fast enough to scrape off some lead from the pellets. And some barrels seem more prone to scrape off lead than others. That, alone, is the sole cause for buildup in an airgun.
In contrast to a firearm, an airgun can be fired tens of thousands of times between cleanings…and some lower-velocity airguns may never need cleaning at all. Those with brass or bronze barrels are entirely impervious to cleaning requirements.
The time to clean your airgun is when the accuracy falls off, not before. Do not clean an airgun barrel on a regular schedule — they simply don’t need it.
2. Disassembly without a plan
I’ve done this and so have many of you. The gun isn’t working right, so we take it apart to find out why. Then, we haven’t got a clue how to get it back together. That results in a basket case of parts that somebody else will be able to buy for a song. Don’t create bargains for others! Before you take an airgun apart, give some thought to what it takes to put it together again.
The way to do this is to first research the gun on the internet, to see if there are any disassembly or assembly problems. If there are known issues with a gun, there should be plenty of information on the internet.
Another thing to look for is if any special tools or equipment are needed. With spring guns, you usually need a mainspring compressor to safely disassemble and assemble the gun. And if you’re disassembling a BB gun like a Daisy Red Ryder, you need to make a special fixture to hold the gun while the mainspring is compressed and parts are removed. Unless you have three arms, this fixture is absolutely necessary.
Then, there are guns that are assembled during manufacture in ways that make them almost impossible to repair. One good example of this is the barrel of a Benjamin 392, which is soldered onto the pump tube at the factory. If the solder joint is ever broken, it’s next to impossible to repair. That’s because the joint is very long and is difficult to keep an even heat on the entire joint at the same time. The solder flows in some places, but clots in others. When you move the heat to the places where it’s clotted, you lose the solder that flowed before.
Don’t attempt repairs or modifications unless you know you can do the entire job. Better to spend some money to get the job done right by an airgunsmith than to charge in and break or lose some irreplaceable part.
Some of the new owners’ manuals tell people to oil the compression chamber on a frequent schedule. While oiling was appropriate for guns with leather piston seals, the newer synthetic seals don’t need nearly as much. Over-oiling causes detonations that can damage the gun if they’re allowed to continue; and once they start, there’s almost no way to get them to stop. All spring guns diesel; but when they go off with a loud “bang,” that puts a strain on the mechanism.
I always like to err on the side of under-oiling because all that does is make noise during cocking. Over-oiling causes problems, though, and in extreme cases the airgun must be disassembled and dried out.
There are places to oil besides the compression chamber. Linkages need a drop every now and then, and the wood parts can always benefit from a Ballistol wipedown.
The other place oiling is necessary is on the tip of each fresh CO2 cartridge before it is pierced. The best oil for this job is Crosman Pellgunoil, and a CO2 shooter needs to always have some on hand. The oil is blown through the gun’s valve when the cartridge is pierced; and it gets on all the sealing surfaces, making a tight seal against gas loss. It’s the No. 1 maintenance action a CO2 gunner can take, and you absolutely cannot overdo it.
So, what happens when an airgun is not oiled enough? It makes noises to tell you. Spring-piston guns will honk like a goose when they’re cocked if there isn’t enough oil on the piston seal. Mainsprings will crack and crinch when cocked as they slip their coils when they don’t have enough oil. And the fork that the breech sits in will become shiny if there isn’t enough grease between it and the breech. Also, the cocking effort will increase dramatically.
CO2 and pneumatic guns will develop slow leaks when they need oil. Their seals cannot do the job without a thin film of oil on all their surfaces. But if the gun is holding air, stop with the oil — except in the case of CO2 guns, as noted before.
This fault is as old as the hills and is a classic mistake a newcomer will make. If 10 pump strokes give X amount of power, shouldn’t 15 pump strokes give 1.5X? No! In fact, they do just the opposite. Over-pump a pneumatic or overfill it from a scuba tank, and the velocity takes a nosedive. It will drop all the way to zero, at which point the valve is locked shut by the excessive pressure in the gun. Imagine a door being held shut by several strong people. No amount of pushing will open it. You have to wait for some of the people to leave or, in the case of the gun, for some of the internal pressure to drop. That can take weeks and even months!
A pneumatic gun is designed to work within a certain pressure margin. Too little pressure and the power drops. Too much pressure and the power drops. Remember it this way — putting more gas into a car’s tank will not make it go any faster.
With CO2, you don’t have to add pressure; and in fact, there’s no straightforward way to do it. If you were to increase the gas pressure somehow, all that would happen is more gas would condense to liquid. The pressure would remain the same. But if the outside temperature should go up, the gas pressure will increase as well because the gas pressure is dependent on temperature. Operate your CO2 guns when the temperature is between about 60 degrees and 90 degrees F. And don’t leave a CO2 gun lying in the direct sun, even on a relatively cool day, because the gun will absorb the sun’s heat and will go into valve lock.
There you go — 5 simple things to remember about airguns and their operation. Perhaps our readers can suggest more?
by Tom Gaylord, a.k.a. B.B. Pelletier
Let’s begin testing the effects of oiling pellets. There are numerous ways to approach this issue, and I have to pick one at a time and limit the test to just that. But I think as long as I’m testing one aspect, I ought to test it thoroughly so someone can’t come back and second-guess me later in the report.
So, today I’ll test with one rifle, and the next time I’ll test with another. What I won’t do is test with each different brand of airgun, just to see what will happen. If a powerful gas spring rifle performs in a certain way, I’ll assume that all powerful gas spring rifles are going to do the same. If the difference between dry pellets and oiled pellets is close, I may do additional testing; but if there’s clear separation, I’ll accept that as the way it works.
What am I testing?
The question that started this experiment was, “How much faster will oiled pellets shoot than those that are not oiled?” One reader has asked me to also test this downrange because he wonders if a thin coat of oil changes the laminar flow of air around a pellet. I may get to that at some point, but for the present I’m just concerned with muzzle velocity because all pellets slow down after they exit the muzzle — oiled or not.
I suppose this needs to be tested in all three powerplant types, but today I’m testing it in a spring-piston powerplant. Today’s gun is a weak powerplant, so next time I’ll test it in a more powerful gun.
I’m using an HW55 SF target rifle to test three pellets. This rifle is a variation of the old HW50 rifle, so it shoots in the 600-650 f.p.s. region with lead pellets.
Since oiled pellets will leave a film in the bore, I tested all pellets dry first, and then tested the oiled pellets afterwards. Before the first test shot with oiled pellets, I fired two pellets to condition the bore. That turned out not to be enough, but I’ll come to that later.
I’ll test the three major pellet shapes in this test. They’re the wadcutter, dome and pointed head. There are other shapes, like hollowpoints, but they’re based on one of these three main shapes, so this is all I’m testing.
How I oil pellets
I oil pellets in the following manner. A foam liner is placed in the bottom of a pellet tin, and 20 drops of Whiscombe Honey are dropped onto the foam. Then, a single layer of pellets is spread on the foam, and the tin is rolled around. I shake the tin lightly to move the pellets around…but not enough to damage them. Whatever oil transfers to the pellet is all the oil it gets. I’ve been doing this for many years and it works well.
The pellets end up with a very light and uniform coat of oil. When I handle them the tips of my fingers become oily, but I can’t see any oil on the pellets. Other people use more oil than I do, but this is what I am testing.
Whiscombe Honey is a mixture of two-thirds Hoppes Gun Oil (not Number 9 bore cleaner!) and one-third STP Engine Treatment, by volume. Shake the mixture until is takes on a light yellow color. It will look like thin honey, hence the name. This mixture should not detonate easily in a spring gun.
Test one — dry pellets
Crosman Premier 7.9-grain pellets were the domes I tested. The average velocity for dry Premiers was 606 f.p.s., with a low of 577 and a high of 616. So, the spread was 39 f.p.s. The average muzzle energy was 6.44 foot-pounds.
For wadcutters, I tested Gamo Match pellets. The average for dry pellets was 652 f.p.s., with a low of 640 and a high of 663 f.p.s. The spread was 17 f.p.s. The average energy was 7.14 foot-pounds.
H&N Neue Spitzkugel
The pointed pellet I selected was the H&N Neue Spitzgugel. When shot dry, they averaged 601 f.p.s., with a low of 585 and a high of 620 f.p.s. The spread was 34 f.p.s. The average muzzle energy was 6.81 foot-pounds at the muzzle.
Now, I shot two oiled pellets through the bore to condition it and began the test.
Oiled Crosman Premiers
Oiled 7.9-grain Premiers averaged 591 f.p.s., but the spread went from a low of 545 to a high of 612 f.p.s. That’s a spread of 67 .p.s. The average energy for oiled pellets was 6.13 foot-pounds. I did notice the pellets were going faster at the end of the shot string, so I thought I might come back to them after testing the other pellets.
Oiled Gamo Match pellets
The oiled wadcutters averaged 658 f.p.s. — a slight gain over the dry pellets. But the real news was the spread, which went from a low of 651 to a high of 663 f.p.s. Instead of a 17 f.p.s. for the dry pellets, the oiled pellets gave a spread of just 12 f.p.s. That’s too close to draw any conclusions, but it’s interesting. The average energy with the oiled pellets was 7.27 foot-pounds. So, with the oiled pellets, the velocity went up — along with the energy — and the shot-to-shot variance went down.
Oiled H&N Neue Spitzkugel
Oiled Spitzkugels averaged 609 f.p.s. — which was a small increase over the same pellet when dry. The average energy was 6.99 foot-pounds. The spread went from 585 to 620 f.p.s, which was identical for the same pellet dry. Velocity and energy were both up slightly from dry pellets, and the shot-to-shot variance remained the same.
By now, it’s obvious that the bore needed more than two shots to condition it, so I retested the oiled Crosman Premiers. The second time the oiled pellets averaged 604 f.p.s., which is just 2 f.p.s. slower than the same pellets dry. But the spread that was 67 f.p.s. on the first test of oiled pellets and 39 f.p.s. with dry Premiers now went from a low of 594 to a high of 613 f.p.s. — a much tighter 19 f.p.s. total. The average energy was 6.40 foot-pounds.
From this test, I observed that these three pellets either remained at the same velocity or increased very slightly from the light oiling I gave them. In two of the three cases, the velocity spread got tighter when the pellets were oiled.
I further observed that it’s necessary to condition a bore with oiled pellets before doing any testing. As a minimum, I would say that 20 oiled pellets should be fired before testing.
These are very small differences from oiling; and although I can’t draw any conclusions yet, I would think that such a small change is not enough to matter. It hardly seems worth doing at this point. However, there’s still a test to be done in a powerful airgun. Until we see those results, I think it’s too soon to say anything for sure.
Although the question that drove this test was how much faster oiling pellets makes them shoot, I think we still have to take accuracy into account before forming any opinions.
And now for something completely different
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Directs and coordinates activities of the department in providing customers technical services and support; directly supervises employees. Responsibilities include but are not limited to:
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Establishes and documents department procedures and objectives.
Accomplishes department objectives by selecting, orienting, training, assigning, coaching, counseling, and disciplining employees; communicating job expectations; and monitoring performance.
Maintains and improves support operations by monitoring staff and system performance, identifying and resolving problems, and preparing and completing action plans
Provides technical assistance to customers and labor quotes. Handles escalated calls or provides assistance requiring more complex issues.
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by Tom Gaylord, a.k.a. B.B. Pelletier
This report will be lengthy because I want to test several aspects of oiling pellets. For starters, I want to test it with spring guns, PCPs and CO2 guns just to get a complete picture of what, if anything, oiling pellets is doing in each of those powerplants. I’m interested in velocity because of the question that spawned this blog, but accuracy might also be interesting to test.
We received this question in the following form. I will paraphrase, but this is the gist of it, “How much faster do pellets go when they are oiled?” That question came in on one of our social networks and was referred to me for an answer. Well, you know me! Give me a topic and I turn it into a week’s worth of blogs. But this question really begged for the full treatment because there’s so much to cover.
When I got interested in shooting airguns as an adult in the middle 1970s, the question of oiling pellets wasn’t around (as far as I know). In talking with the late Rodney Boyce, I learned that the oiling question really came to a head when PCPs first started being used in the early 1980s. A PCP shoots very dry air, and their barrels are made from steel; so, at the higher velocities, they tend to get leaded bores. Some shooters were also oiling pellets for their spring guns; but a lot of the time they did it because they washed the pellets, thinking the black compound on them was dirt. In fact, it was anti-oxidant to keep the pellets from turning to white dust. Had they just left the pellets alone, they wouldn’t have oxidized.
In defense of the spring-gun guys who washed their pellets, though, some brands did have a lot of lead swarf (flakes of lead from the manufacturing process) inside some of the pellets, and vigorous washing did remove it. But then the pellets needed to be oiled again, or they would quickly oxidize.
Why we oil pellets
We oil pellets for two reasons. The first is to prevent the oxidation of the lead after washing. The second is to reduce the leading of the bore, though this is principally a PCP problem. Other pneumatics either shoot too slowly or they have brass or bronze barrels that do not allow the lead to attach itself, so they do not lead up.
Do oiled pellets shoot faster?
That was the question that started this report. I’ve tested this in the past and found that with a PCP shooting .177 pellets at 850-900 f.p.s., oiled pellets went slower, not faster. But that was just one test, and I don’t want to say what oiling will do for other guns until I do some more testing.
I’ll tell you this — oiling pellets became such a hot topic in the late ’90s that people were swapping their favorite secret formulas on the internet. And I know one UK company that sells an oil for pellets that they still claim gives increased velocity. Well, that’s too good to pass up, so I’ll test some of their oil in this test.
Not just oil
Don’t think that oil is the only thing people put on pellets. I remember lengthy discussions of how to apply a thin even coat of wax on pellets. Then, the topic shifted to what kind of wax to use! One guy went so far as to specify a high-tech boat hull compound called Bo-Shield for his pellets. When he talked about it his eyes got that faraway stare, as though he was transcending the real world and entering the spirit world.
What I will test
The first thing I want to do — have to do, in my mind — is test what the application of oil does to the velocity of pellets. Okay, that opens about 10 worm cans, right there:
What constitutes “an application of oil”? (I have seen paragraphs of instructions telling you how to know if the application of oil has been enough or if you need more.)
Am I testing this on lightweight pellets? Heavy pellets?
Do I test a powerful springer as well as a lower-powered springer?
Do I also test this on a precharged pneumatic?
A powerful PCP and a lower-powered PCP?
What about testing on a CO2 gun?
And on and on….
I think the best approach is to ask the question: Why do we oil pellets and who does it? We know that people who wash pellets also oil them, and we know that PCP users oil them; so that includes all the categories above. I don’t see a need to go to the extremes with this test. I’m not HP White Labs, and this isn’t a burning consumer question. If the findings suggest further testing, I could decide at that point?
What about the possible side effects?
Will oiling a pellet cause extra dieseling? Maybe. Is that what’s behind those flimflam salesmen who claim that oiled pellets go faster than dry pellets? I don’t know for certain; but as long as I’m going down the path, this is something I want to look at. Obviously, we’re talking only about powerful spring guns.
Does oiling affect accuracy?
I don’t know, but it seems we ought to find out. This gives me another excuse to unlimber my R8…so, hurrah!
Have I forgotten anything?
You tell me if I’ve overlooked any test that ought to be conducted. This isn’t a guessing game or a creativity contest, so please tell me only things that really matter to you.
by Tom Gaylord, a.k.a. B.B. Pelletier
El Gamo 68 is a futuristic breakbarrel from the past.
I last reported on this rifle on August 8 of last year. And that was Part 5! I had just tuned the rifle with a new mainspring and proper lubricants and was wondering what the changes would be. I was ready to report on it several months ago when I discovered that it wouldn’t cock. After fiddling with the trigger adjustments awhile with no success, I set it aside and moved on — thinking that the gun would need to be disassembled.
I disassembled it last week and discovered there was nothing wrong! The sear was working properly, or at least it seemed to be when I played with it as the gun was disassembled. I relubricated everything and put it all back together and was going to write Monday’s report on it. But the trigger still didn’t work! ARRGH!
This time, I remembered that when I got the gun the trigger was also a bit iffy, so I fiddled with the adjustments WAY outside the normal realm and, presto! I got it working again. Oh, it took a couple hours and there were some accidental discharges when the barrel was closed (direct sear!), but I solved all that by giving the sear way more contact than it needs.
Now the trigger releases at about 12 lbs., but at least it’s safe. Today, I’ll share with you how the tuned gun does at 25 yards — heavy trigger and all.
One other thing I did to the rifle was lubricate the leather piston seal with 10 drops of 3-in-One oil, leaving the rifle standing on its butt for two days afterward. The oil was allowed to slowly soak into the leather, which it did, but to protect the carpet and walls (Edith–Are you listening?) I put a long drop cloth in front of the rifle when I shot it.
Today’s test is a deviation from my normal pattern. I’ve tuned this gun and not yet reported the new velocities, and yet here I am shooting for accuracy. I decided to do it that way; and if I got good results, I would test the velocity next. I’m not changing the usual way of doing things — this is just an exception.
The first pellet I tested was the RWS Hobby. I chose it for its light weight and because it’s often accurate in lower-powered spring rifles and pistols. Sitting 25 yards from the target, I have to admit that I was wondering if the rifle had enough power to hit that target — let alone shoot a decent group.
Five of the first 10 pellets were detonations from the oiled piston seal. And the smell of burning oil was in the air. The Hobbys landed in a vertical group that was pleasingly tight from side to side. I was prepared to blame the verticality on the dieseling, but the truth is, that wasn’t the problem. The gun just doesn’t want to shoot Hobbys at 25 yards. That’s not too surprising since 25 yards is about the maximum distance for any wadcutter pellets, in my experience.
Air Arms Falcon
The second pellet I tested was the Air Arms Falcon, a 7.3-grain dome that’s often accurate in spring rifles. I used the spotting scope only on the first shot, which was a detonation, to make sure it was on the paper. There were 4 detonations in the 10 shots. I didn’t look at the target again until I walked down to change it. Boy, was I surprised by what I saw! To paraphrase Crocodile Dundee, “Now, THAT’S a group!” For open sights at 25 yards and 65-year-old-eyes, it ain’t too bad!
Remember, I’m shooting 10 shots — not 5. So this kind of group really proves the rifle can shoot. It also proves this old man can still hit things when the rifle does its part! So much for the problems of the droopers and gas springs! I needed this validation after some of the disappointing tests I’ve done recently.
The heavy trigger apparently is not causing much of a problem for me. I think that’s because the rifle is rested. If I were shooting offhand, I’d want a lighter trigger-pull.
JSB Exact RS
Next, I tried JSB Exact RS pellets. This is another 7.3-grain dome from JSB (JSB also makes Air Arms Pellets) and is very often accurate in many different airguns. And this is one of them. The group is slightly larger than the Falcon group, but the two are so similar that I would call it a tie.
The last pellet I tried was the RWS Superdome, which often does well in lower-powered spring rifles. This time, however, it didn’t. Ten pellets produced a 1.765-inch group. It didn’t disappoint me, though, because the Falcon and JSB RS groups looked that much better. It showed that the earlier Hobby group wasn’t just a fluke of bad luck — the gun simply likes what it likes.
This test was calming for me. It was slower than many of the tests I’ve run in the past month, and the results were more based on me as a shooter rather than on the equipment. I find that I like that a lot!
The El Gamo 68 XP is operating well right now, except for the heavy trigger that I’ll probably keep just as it is for a while. The tuned powerplant is now smoother with less of a jolt. I noticed in this test that each pellet has a firing characteristic of its own. The two JSB pellets were definitely the smoothest of the four tested, and the Hobbys were the roughest.
This is such an odd airgun, with the fat heavy butt and no forearm to hold. Yet, it shoots like a thoroughbred. With the new tune, it cocks smoothly and just feels good to shoot — I don’t have any better way of describing it. I wish you could all try one, but since you can’t, I will, again, recommend the Air Venturi Bronco, which is the closest thing still being made today.
by B.B. Pelletier
Last week, our new reader, Cantec, mentioned that several gentlemen were advising the use of corn oil for lubricating the compression chambers of spring-piston airguns. I know exactly where this recommendation came from and how it should be viewed, and I wanted to share this with you today.
Yes, I’m talking about common corn-based cooking oil. Wesson oil is the most popular brand here in the U.S. Why would anyone recommend using corn oil in a spring-piston airgun? I want you to know the entire truth so you don’t make any serious mistakes with your guns.
Good old corn oil that’s most often used for cooking has also been used to lubricate some spring-piston airguns.
In my role as a firearms enthusiast, I used to put WD-40 on all my guns. It smells so good and guns always look so nice after they have been wiped down with it. So, when the Army sent me to Germany for four years, I sprayed WD-40 on all my guns before storing them in my mother’s attic, thinking I was protecting them against the ravages of time. What happened, instead, was that the WD-40 dried out and left every gun covered with a thick coating of yellowish residue that proved nearly impossible to remove. Only more WD-40 would dissolve it, and in one case the silver plating on my collectible second generation Colt 1851 Navy cap and ball revolver was destroyed! Each gun took weeks to clean, because the residue had gotten into all the cracks and tight places and had to be scraped out with tools.
Several years after that experience, I joined an horology club and attended their meetings for about a year. These are guys who fix watches and clocks, and they had one thing to say about WD-40. Don’t ever use it on a clock! They knew all about the yellow coating it leaves, and several members had horror stories about removing it from clock gears. Apparently, not even ultrasound tanks can remove all of it.
Before you rise up to defend WD-40, know that I use it, too. For certain jobs, it can’t be beat. But not for protecting the finish of a gun. Use Ballistol for that.
What does WD-40 have to do with corn oil? Everything. Like WD-40, corn oil dries and leaves a waxy film on anything it comes in contact with. And that’s why it was originally recommended for spring-piston airguns. Not all spring-piston guns, you understand. Just the ones from China.
Duane Sorenson, who used to work at Compasseco in the 1990s, recommended corn oil for all his Chinese guns because of the waxy buildup. He reasoned that the wax filled in the rough machining marks left inside the cheap Chinese compression chambers, eventually building up to the point that compression increased. He was an active proponent of corn oil in spring guns, and I think many thousands of shooters were told by him to use it.
Duane also said the flashpoint of corn oil was very high, so using it would stop dangerous detonations. As far as I was able to test for that, it did seem to work. But — and this is the point of today’s report — corn oil is not recommended for a sophisticated spring-piston airgun powerplant. The current crop of Tech Force guns do not have compression chambers rough enough to benefit from its use.
Time is the criterion
Duane was advising corn oil for airguns like the B3 underlever and the TS45 sidelever. Those guns really did have rough compression chambers that could benefit from a product that infilled their machining marks. But at the same time he was recommending corn oil, Sorenson was also pushing their Chinese manufacturing partner to better finish the insides of their compression chambers. The result was the Tech Force 36 underlever, which was very smooth inside, and later the Tech Force 99, which was even better.
But while this improvement was happening, Duane was still selling lots of the older and less expensive Chinese spring guns that were still very rough. So, he continued advocating corn oil, even as the many of the guns he sold were getting better and had less need for it.
I tested it
Duane was so insistent on corn oil being a miracle-product that I bought a quart of the stuff and began experimenting with it. That was how I learned that it doesn’t detonate. While I was testing it, I was unaware of why corn oil was being recommended and the fact that many of the more modern chinese airguns didn’t need it.
I conducted several tests using corn oil for The Airgun Letter, but frankly I never got the kind of results Duane told me to expect. Part of that was because I was probably testing it on the wrong guns and part was because I wasn’t using it as much as Duane did. I never saw the long-term effects he told me about.
I expected to see an increase in velocity and a decrease in the total velocity variance. The velocity never increased as much as I had thought, but the shot-to-shot variation did decrease somewhat.
What about corn oil today?
This is the reason I wrote today’s report. Do not use corn oil in any modern spring-piston airgun! Corn oil is meant to solve a level of manufacturing crudeness no longer seen in modern airguns. Like many other things, time has changed the game. We no longer put oatmeal in our car radiators to patch small leaks, and we certainly no longer lubricate spring-piston compression chamber with corn oil.
Just as you don’t want a buildup of hard yellow film on the outside of your airguns from dried WD-40, you also don’t want the waxy buildup from corn oil on the inside. Use the products that are recommended for the job, like a proper grade of silicone chamber oil for the compression chamber of your airguns.