Posts Tagged ‘spring-piston’
by Tom Gaylord, a.k.a. B.B. Pelletier
Last week, I made reference to a heavy top hat affecting performance in a spring gun, and blog reader Joe asked this question:
“You wrote ‘…weighted top hat inside the piston, or the piston itself is heavy. Either way, the rifle should shoot medium and heavyweight pellets better than lightweight pellets.’
What is a ‘top hat’? Why would a heavy piston or top hat shoot medium to heavy pellets better?”
Joe, thank you for asking this question. This blog is now in its 10th year, and I forget that the readership has changed over that time. If one person asks a question, it means that many other readers are wondering the same thing and not writing in. Today, I’d like to review the main parts of a spring-piston airgun powerplant and discuss how they affect performance.
The piston is the most recognizable part of the powerplant. When the gun fires, it’s propelled forward by some kind of spring. It may be a coiled steel spring or it could be some kind of gas under pressure — whatever the source of energy is, it pushes the piston. And before anyone asks — yes, there have been guns with springs that pull the piston.
The piston compresses air in front of it as it goes forward. There is some kind of seal on the piston that keeps most of the air contained, so it compresses air very well.
The piston seal (this one is a parachute type, whose sides flare out and seal the chamber better) seals the air in front of the piston.
Removing excess tolerance makes a spring gun shoot smoother. The top tuners put Teflon or nylon bearings (called buttons) around the rear of the piston skirt to hold it steady and away from the spring tube walls. The piston seal does the same thing for the front of the piston. In a well-built airgun, the metal piston should never touch the walls of the spring tube.
These small white nylon bearings on the Benjamin Nitro Piston 2 are part of the reason that rifle is so smooth when it fires!
Let’s talk about something that’s dirt-simple, yet confuses a lot of people — the compression chamber. It’s the end of the spring tube, which has been closed off by a metal cap. A hole through the cap, called the air transfer port, allows the compressed air to move from the compression chamber to the barrel. If there’s a pellet in the barrel, the air cannot get past it and has to shove the pellet out of the way. This doesn’t happen until the air reaches a high pressure, which is at the heart of today’s discussion. Essentially, the pellet stays put until the piston has come to almost a full stop, then the compressed air blows it forward, like the cork from a champagne bottle.
The spring-piston powerplant is so simple that it confuses people.
We all know what the spring does. It pushes the piston, which compresses the air. A spring can be either coiled steel or compressed gas; but for the remainder of this report, I’ll be talking about a coiled steel spring because it’s the thing that relates to the top hat.
Thanks to a generous cocking slot, we can see the mainspring inside this piston’s body.
The spring guide does what the name says — it guides the spring. What it actually does is keep the coiled spring from twisting or bending too much as it’s compressed.
This is the spring guide. It’s hollow to allow the piston rod to pass through when the gun is cocked. The metal one is an older Beeman R1 guide, the white plastic (probably nylon) one is what they use more often these days. A lot of vibration can be eliminated by very closely fitting this guide to the inside of the spring.
When the gun is cocked, the piston comes back and compresses the spring. The spring fits up inside the piston, so it’s contained by the piston skirt as the piston comes back over it. The spring guide is a hollow tube at the rear of the spring that the spring fits over. As the spring is compressed, it tries to bend to the side, but the spring guide prevents it. The piston skirt keeps it from bending at the front.
When a tuner wants to smooth the performance (the shot cycle) of a spring gun, getting rid of excess clearance is a great way to eliminate vibration. The outside of the mainspring is fitted to the inside of the piston skirt very closely. Here’s something you may not have guessed. When the spring is compressed, it also expands just a little (measured in thousandths of an inch), so the internal fit to the piston skirt has to take that into account.
The spring guide is also fitted to the inside of the mainspring. In the best-tuned airguns, the guide cannot be put on the spring unless the spring is twisted against the guide counterclockwise. Airgunsmith Jim Maccari calls that a guide that’s “nailed on.” The mainspring grows in diameter as it’s compressed. When the gun is cocked, the spring loosens a little and slips down the guide.
Top hat (forward spring guide)
Okay — here it is. You had to wade through lot of blather to get to this point, but I hope it’ll be worth it. A top hat is a spring guide that is on the front side (the piston side) of the spring. It fits inside the piston and slides on the central piston rod. Obviously, the mainspring fits over this guide, too, just like it fits the guide in the rear.
Two top hats (forward spring guides). The heavier one at the bottom was made by airgunsmith Jim Maccari for a special Beeman R1 tune that worked for heavier pellets. I wrote about it in the “Beeman R1″ book.
Joe — this is the answer to your question. A top hat adds weight to the piston. A heavy top hat adds a lot of weight.
When the piston compresses the air in the chamber, it can reach very high pressure before the pellet starts moving. When the pellet begins to move, the air pressure drops rapidly. Although the pressure is very high, there’s not a lot of it — pressurized air.
If the pressure in the chamber is too high and the pellet hasn’t started moving, either because of its size, weight or both, the piston can rebound off the compressed air cushion and travel backwards a few hundredths of an inch before the pellet starts to move. Heavier pellets will resist moving longer than lighter pellets — I hope that’s obvious.
By adding a lot more weight to the piston, it can resist rebounding to a greater degree (because of its greater inertia). Heavier pistons usually do better with heavier pellets. And top hats are one way to make pistons heavier. That’s why I said what I did.
That was a quick and dirty look at the spring-piston powerplant and some of its subtleties. Don’t think this makes you an expert — there’s a whole world of things like this that I haven’t addressed.
by Tom Gaylord, a.k.a. B.B. Pelletier
Falke model 70 is a quality breakbarrel spring-piston rifle from the 1950s.
Today is accuracy day for our Falke model 70 breakbarrel. I tested this one at the same time I tested the BSA Meteor Mark IV; and after that horrible test, I was praying that this rifle wouldn’t let me down. When I bought the rifle at last year’s Roanoke airgun show, the seller told me it shot pretty well. I was hoping to see that — especially after what happened with the Meteor! It did okay in the velocity test, so there was no reason to suspect it wouldn’t also be accurate.
The Falke did not disappoint, though it’s important to bear in mind that this is a vintage spring rifle made by a company that went out of business a half century ago and not some tackdriver made by a target gun manufacturer. When you shoot one of these air rifles, think in terms of a vintage Diana model 27 rather than a Walther model 55.
The Falke has open sights, so I like to start testing guns like them at 10 meters. They’re usually right on target; but if they’re off, 10 meters is close enough that they won’t be off that much. Open sights seldom have the same kind of problems as optical sights.
The Falke is a vintage airgun, so I felt it deserved a vintage pellet — at least for starters. The first pellet I tried was the Eley Wasp. Of course, I also tried Wasps with the Meteor and look where that got me! But the Falke was far more forgiving. In .177 caliber, the Wasp pellet is medium-sized — nothing like the oversized 5.56mm (.22 caliber) Wasps pellets we use in guns that have large bores. Wasps fit the Falke 70 breech well, but they weren’t tight. They didn’t fall out, but they also didn’t need to be pushed into the rifling. They went in easily.
When I saw the group, I was amazed! Eight of the ten Wasps were in a tight group that measures 0.276 inches between centers. The 2 pellets that aren’t in the main group open it to a much larger 0.862 inches, but I’m thinking those 2 shots might have been due to small sighting variations.
Eight of ten Eley Wasps went into a tight 0.276 inches, but the final 2 opened it to 0.862 inches.
The rifle has a comfortable feel when shooting. I’d called it a single-stage trigger, but it’s actually 2-stage. Stage 2 is very subtle and takes some time to get used to it to feel it every time, but it breaks cleanly enough for good work. The post-and-bead front sight is somewhat difficult to use precisely; but at 10 meters against a black bull (with a 6 o’clock hold), it’s good enough.
I like the way the breech locks when it closes. The spring-loaded lock breech jumps into position. After it does, you cannot feel any movement in the breech.
After the Wasps, I adjusted the rear sight higher to get into the bull. Then, I started a group with RWS Hobby pellets; but after just 3 shots had gone into 1.371 inches, I gave up. No sense finishing a group like that! Hobbys are often a very accurate pellet in vintage airguns of the same power as this Falke model 70; so it was worth a try, but when things go that wrong that fast it’s time to move on.
Crosman Premier lites
Next, I tried the 7.9-grain Crosman Premier lite pellet. This is another pellet that often does well in lower-powered spring guns like the Falke 70. But not this time! Ten went into a group that measures 1.164 inches between centers. You might wonder why I was so quick to abandon Hobbys yet stuck with Premier lites to the end. Well, this group just kept growing larger with each shot. It wasn’t until close to the end that I saw how large it was going to be.
Air Arms Falcons
Next, I tried some Air Arms Falcon pellets. The Falcon is a 7.33-grain domed pellet made for Air Arms by JSB on dies that Air Arms owns, so it’s unlike anything else JSB makes. It’s too simple to say the Falcon is just a JSB Exact RS under another label; for although both pellets weigh exactly the same and are both domed pellets, they don’t perform the same. Often Falcons will shoot well when Exact RS pellets won’t.
In the Falke 70, they did pretty good! Of course, I didn’t miss the irony of shooting a falcon pellet in a falcon rifle!
For starters, they went to the exact center of the bull. I know this thrills some folks who need to see the pellets impact there; but like I always say, I’m looking for the smallest groups — then, I’ll adjust the sights later. But when luck happens and I get this result, I can’t deny that it thrills me a little. Ten pellets went into 0.762 inches, which is okay but not great. But within the main group there are 7 pellets that made a much smaller group measuring 0.387 inches. Like the Wasps, I cannot help wondering if I could do better.
H&N Baracuda Match
The last pellet I tried was the H&N Baracuda Match. While this seems like an overly heavy pellet for such a low-powered spring rifle, I’ve found they often do quite well in some guns. They were certainly worth a try. Although the rear sight was adjusted up for most of the other pellets, the Baracudas hit low on the target. But they did put 8 of 10 into 0.44 inches, which is very good. And, again, there are 2 pellets that didn’t want to go into the main group. They opened the group to 0.742 inches, making this pellet the most accurate of those tested.
Should I test at 25 yards?
The Falke model 70 will never have a scope. I sense the accuracy potential of the rifle exceeds the precision of the sights. Two and perhaps even 3 of these groups should have been one small hole, but for sighting errors. I am tempted to back up to 25 yards and have a go. We shall see.
by Tom Gaylord, a.k.a. B.B. Pelletier
Falke model 70 is a quality breakbarrel spring-piston rifle from the 1950s.
Today, I’ll test the velocity of the .177-caliber Falke model 70 breakbarrel. In its day, which was the early 1950s, this rifle was rated at 450 f.p.s. But pellets have improved a lot since that time, and I also believe this powerplant has been rebuilt. So, the numbers may not be the same as a factory gun.
The first pellet I tested was the 7.9-grain Crosman Premier lite. For the first test, I seated the pellet flush; but given the probable power range of this rifle, I felt that some deep-seating would also be worth trying. Premier lites averaged 634 f.p.s. in the initial test (seated flush). The range went from a low of 621 f.p.s. to a high of 646 f.p.s. So, the spread was 25 f.p.s. That’s not bad, but I’ve certainly seen better. At the average velocity, this pellet generated 7.05 foot-pounds of energy at the muzzle.
Next, I tried the same pellet seated deep with the Air Venturi Pellet Seater. This time, the average velocity climbed up to 651 f.p.s., with a spread from 640 to 660 f.p.s. So, greater velocity and less variation with this pellet seated deep. At the average velocity, this deep-seated pellet generated 7.44 foot-pounds of energy at the muzzle.
The next pellet I tested was the RWS Hobby. This one I seated deep from the start. The average velocity was 704 f.p.s., and the range went from a low of 684 f.p.s. to a high of 721 f.p.s. That’s a spread of 37 f.p.s. in just 10 shots, which is getting a little large! At the average velocity, this pellet generated 7.71 foot-pounds of muzzle energy.
Because the velocity spread was so large, I figured I would also test this pellet seated flush. But after shooting just 4 shots, I had a velocity variation of 49 f.p.s., so I stopped. Obviously, the Hobby doesn’t like to be seated flush in the Falke 70.
H&N Baracuda Match
The last pellet I tried was the heavy H&N Baracuda Match. Weighing 10.65 grains, this pellet might seem too heavy for a spring rifle in this power class, but I’ve seen pellets like this shoot very well in some of these guns. In case that happened here during the accuracy test, I wanted to have the velocity on record. These pellets were seated flush.
Baracuda Match pellets averaged 508 f.p.s. in the Falke, and the spread went from a low of 503 to a high of 515. That’s just 12 f.p.s. — the tightest spread of the test. Because they’re so tight when seated flush, I decided to not bother testing them seated deep. I’m pretty sure I will shoot them seated flush.
At the average velocity, this pellet generated 6.10 foot-pounds of muzzle energy. So, the Falke 70 followed the classic spring gun pattern of heavy pellets being less efficient and light pellets being the most efficient.
The single-stage trigger is adjustable, but the adjustment is of the sear-contact area type. So, I’m leaving it alone. It’s light enough as it is right now, breaking at just 1 lb., 15 oz. The letoff is vague, but the pull is free from creep, so the rifle doesn’t move around a lot when you shoot.
I mentioned in part 1 that the rifle seems to cock easily until the last part of the stroke, when the effort rises significantly. Well, the scale confirmed it. The first part of the stroke is 20 lbs., then the effort spikes up to 37 lbs. to complete the stroke. It’s way more than one might expect from a rifle in this class. That leads me to suspect that an aftermarket mainspring has been installed in an effort to increase the power. I may have to correct that some time, as it’s just too much effort for a plinker like this.
Blog reader RidgeRunner asked me if the rear sight blade had a small spring under it, so I took it apart and told him I would provide a picture of the assembly in this report. Not only did I find the spring he was talking about, I also saw that the elevation wheel is marked off with numbers, so you can keep track of adjustments!
The rear sight blade slides into the base, and the elevating wheel fits into the cutout. The spring fits inside the hollow elevating wheel.
I didn’t notice these reference numbers before taking apart the rear sight. They allow you to record and track your elevation adjustments. Airgunners love neat little features like this!
Seeing those numbers on the elevation wheel made me smile. They’re so unobtrusive and easy to overlook. They’re an airgunner’s version of a secret garden. It’s like knowing how the Coke machines get filled at Santa’s workshop!
Overall, I like this rifle very much. It holds well, locks up tight at the breech, thanks to the breech lock, and the firing behavior is smooth. I even like the trigger. I have a feeling this one will be a keeper!
by Tom Gaylord, a.k.a. B.B. Pelletier
Falke model 70 is a quality breakbarrel spring-piston rifle from the 1950s.
This report is a traditional Friday blog for all you who enjoy the vintage airguns I sometimes get to test. I enjoy them, too, but I try not to put too many into the blog because most readers cannot buy these guns. I don’t want to create a lot of dissatisfaction.
I’ve reported on the Falke 90 underlever that reader Vince was kind enough to repair and tune in his 3-part report, It’s not my Falke. Then, I tested the gun for you in a separate 4-part report titled, Falke 90 test. Well, today I’m starting another report on a Falke model 70 breakbarrel rifle.
The distinctive falcon logo is stamped on the spring tube end cap.
All Falke airguns are uncommon in the U.S., but the models 80 and 90 are beyond rare. From the model 70 on down in declining numbers (60, 50, 40, 30, 20 and 10), however, we encounter a number of more common breakbarrel spring rifles that, while not common, are also not rare. They were never officially imported into the U.S., as far as I have determined, but have entered in a number of ways through private transactions. They’re very similar in quality and performance to their Diana cousins of the same early 1950s timeframe. The separation between the model 70 we’re looking at today and the model 80, while only 10 numbers apart, is the difference between a chicken egg and an egg by Fabergé.
The model 70 might also be thought of as Falke’s answer to the Diana 27. In other words, a plain airgun, but also one with high-quality features like a locking breech and an adjustable trigger. The 70 is slightly larger than the 27. It’s 42-7/8 inches long overall, and that length is helped primarily by the 19-inch barrel. The weight is 6 lbs., 10 oz. The pull is 13-3/4 inches, making it suitable for adults and older children.
When I looked in W.H.B. Smith’s book, Smith’s Standard Encyclopedia of Gas, Air and Spring Guns of the World, I saw slightly different specs for the model 70 listed there. There, the rifle was just 37 inches long, and the photo shows a pistol grip that’s rounded at the bottom. It was also checkered; but because mine’s been refinished, I can’t tell if it may have been originally checkered. I doubt that it was, though, because it’s still robust after refinishing.
The rifle’s barreled action is blued steel, set into a slim beech stock that has European finger grooves on either side of the forearm. The breech seal is leather, giving every indication that the piston seal is leather, as well. The metal on my rifle is turning to a plum-colored patina over the years, and the stock has been recently refinished. It was a good job, but I have no idea how much wood was removed in the process.
The rear sight is adjustable for elevation by turning a centrally mounted wheel, but there is no adjustment for windage. However, both the front and rear sights sit in dovetails that run perpendicular to the bore, so some windage adjustment is possible by drifting them sideways in their slots. The rear sight blade sits loose in the rear sight base, which may affect accuracy when I shoot the gun.
The rear sight adjusts for elevation, only. The sight blade is loose in its mount.
The front sight is a post with a bead at the top — the type the Germans call a Perlkorn. The intent is to put the bead in the center of the rear sight notch and also on whatever you wish to hit. It’s not a precision sight, but it can become more precise if you hold it at the 6 o’clock position on a target. But the movement of the blade that contains the notch will affect things, I’m sure.
The trigger adjusts, too, but I remember getting some sort of warning from airgun collector Don Raitzer at the Roanoke airgun show when I acquired the rifle, so I may not adjust it. Right now, it’s a single stage that has a very long but light pull and no positive indication before it lets off. I’m thinking the adjustment might affect the sear engagement area, and I don’t want to diminish that in any way.
The single-stage trigger adjusts, but I think the sear contact area is affected, so I’m going to pass.
The breech is locked by a spring-loaded lever located on the right side of the breech. To unlock it, press in (push it back toward the butt) on the knurled knob while breaking down the barrel. It takes 2 hands to open the breech. When the barrel’s closed, the lock snaps shut and the breech is solid!
The breech is also notable for having both a pivot bolt and a locking screw that fits into scalloped notches cut into the rim of the bolt head. It’s a hallmark of quality that existed in the 1950s. Oddly, though, the pivot screw only has 2 cutouts for the locking screw to fit; so in its original form, it has to be turned a minimum of 180 degrees every time. Someone has used a small portable grinder to add a small notch where it was necessary, and now the pivot bolt head has a third notch in what seems to be the right place.
The breech is locked and must be unlocked to break the barrel. Note the locking notches in the pivot bolt head. And you can see the articulated 2-piece cocking link in this picture, also.
The cocking link is 2-piece and articulated to allow the rifle to be cocked without a long cocking slot in the forearm. That reduces vibration in the stock, adding to the rifle’s overall feeling of quality when fired.
This is a quality air rifle from the 1950s, and the quality shows through. Compared to modern air rifles, the features on this one far exceed what you normally see. The power is much lower than most of today’s rifles, but that just ensures that the rifle fires smoother.
Of course, there’s no provision for a scope, because when this rifle was made, people weren’t scoping their air rifles. I wouldn’t want to scope it, either. This is just a pure fun rifle that’s light and smooth and fun for the whole day. Why ruin it with a scope?
Smith lists the velocity at 450 f.p.s, but of course that was with the crude heavy pellets of the 1950s. I’m sure a modern pellet will step that up, though; by how much, I can’t say. Someone has at least lube-tuned the rifle recently, so it should be performing its best right now. I note when cocking that the cocking stroke is very short — just past 90 degrees, and the mainspring tension builds very fast in the last half of the stroke. In that respect, this rifle differs entirely from a Diana 27 that cocks with an even stroke and no spring buildup (greater effort required toward the end of the cocking stroke).
I’ve been waiting to test this rifle since the Roanoke show. Until today, I had not fired it once! You and I will get get to explore this fine air rifle together!
While reading the other reports on the Falke 90 I cite above, I discovered that I’d promised to test the 90 with a dot sight to see if accuracy would improve. That was way back in January and, of course, I haven’t done it — yet! Look for that test in the near future!
by Tom Gaylord, a.k.a. B.B. Pelletier
I decided to write this for those readers who indicated they were interested in airsoft to some degree. I know this is an airgun blog, and that means pellet and BB guns — not airsoft, but there are some crossovers. For example, many airsoft companies are now entering the world of steel BB guns. I promise we’re not going to become half-and-half or even one-quarter airsoft; but since there are questions, I feel the need to address them.
History of airsoft
This will be short and sweet. Airsoft came about in the Orient in the 1970s, when the demand for realistic guns that were not firearms was first satisfied. The early designers made their guns shoot 6mm plastic balls that they have since come to call BBs.
The early guns were made to satisfy the needs of collectors to see, feel and even be able to disassemble the guns in which they were interested. So, the early thrust of airsoft guns was for collectors, only. However, the fact that the manufacturers made these guns fire their plastic BBs soon evolved into an entirely different interest. People began conducting wargames with the guns. Instead of paintball, which is very painful when the .68-caliber balls hit flesh, the 6mm plastic balls had almost no impact. Of course, the guns in those days were firing at very low velocities; because it was realism, rather than the gun’s ability to shoot, that attracted buyers.
Once the wargames began, airsoft split off into two directions. The collectors wanted highly realistic guns, and the wargamers wanted guns that were accurate at long distance and would hold up under simulated combat conditions. Some of the early collectible guns sold for thousands of dollars. Indeed, there are still a few of these collector guns being sold today. One example is a very real airsoft Browning Automatic Rifle (BAR) that sells for well over $3000. But the collector market has been far surpassed by the wargamers, who now call themselves skirmishers. Airsoft guns for skirmishes are the biggest sellers in today’s market, which has grown to more than a billion dollars in sales annually.
The BB gun wars
I’ve written several articles about the BB gun wars that were conducted in the United States from the 1890s until the 1960s. The BB gun wars were literally backyard battles fought by teams of kids with BB guns. Every community had them, and each bunch of kids had their own rules. I’ve owned several BB guns with multiple dents in both the wood and metal from the impacts of BBs that are obviously survivors of the BB gun wars.
It’s my contention that the BB gun wars still rage today, but they’re now being fought with airsoft guns. Apparently, there’s a need for people to shoot at each other in mock combat, and airsoft guns seem to fill this need.
Because shooting at people is so emotionally-charged, IPSC shooting has recently become popular. IPSC stands for the International Practical Shooting Confederation. It’s the international extension of practical pistol shooting that began as law enforcement training in the U.S. in the 1960s. IPSC competitors shoot from 30,000 to over 100,000 rounds each year in training and competition, so the game is not for poor people.
Airsoft guns are a wonderful way to get into this competition without spending the kind of money that it costs to shoot firearms. For one-hundredth the cost of firearms, shooters can have the same fun under safer conditions with 6mm airsoft guns.
Airsoft history is rapidly evolving. In just 40 years, it’s gone from pure collecting to wargames and now to practical pistol shooting. Who knows what’ll happen in the next 10 years? What’s obvious, however, is that the technology of the airsoft guns is evolving as fast as the interest is. This is a burgeoning area that’s spending a lot of money to satisfy multiple needs.
Let’s examine the airsoft powerplants so we can see what exists and what’s possible. The first powerplant we’ll look at is the spring-piston.
The spring-piston airsoft powerplant is no different than a spring-piston found in any other type of airgun. A piston is powered by a coiled steel spring and moves forward rapidly to compress a column of air that then drives the airsoft BB. Most airsoft spring-piston guns are repeaters, but they must be cocked for every shot. You sometimes see these repeaters called single-shots because the people writing about them don’t understand the difference between a true single-shot that only holds one round and a repeater that holds many round but must be cocked separately to fire each one.
Spring piston guns are among the least expensive, and yet they can also be very powerful and accurate. Sniper guns are powered by spring pistons for the most part. The lowest-powered spring-piston guns cost very little and are not built to last a long time. They have a lot of plastic parts that eventually do wear out. But if you don’t abuse them, most will give you many thousands of shots that will be surprisingly accurate.
Gas airsoft guns are very similar to gas airguns, except they do employ a wider range of gasses. Besides CO2, which they’ve begun to use in the last 15 years, airsoft guns also use other industrial gasses that go by colorful trade names. Green gas and red gas are 2 of these; and green gas is, by far, the most popular. Green gas is nothing more than propane, though some suppliers do infuse some oil into the gas to help lubricate the airsoft mechanisms.
Green gas runs at a nominal pressure of 115 psi. It’s supplied in dispensing cans that have nipples that couple with the inlet valves of the guns they serve.
Someone asked me if green gas was as powerful as CO2, which is pressurized to 850 psi and higher. Well, it isn’t. But that doesn’t mean very much, however, because CO2 has to be stepped way down to safely operate an airsoft gun. The same gun can use both green gas and CO2, it just needs two different magazines — each with its own valve to handle the correct gas.
Generally speaking, gas guns tend to be faster than spring-piston guns, but that isn’t always the case. There are bolt-action spring-piston sniper guns that are very powerful. It’s impossible to make a blanket generalization.
Automatic-electric guns (AEGs)
AEGs are spring-piston guns that are powered by small high-torque electric motors. The motor cocks the piston and trips the sear. The gun usually has a selector switch that allows full-auto (the motor repeatedly cocking and releasing the piston as long as the trigger is held down) and semiauto (firing one time per trigger pull). Besides the spring-piston side of this powerplant, there’s the electric side that deals with batteries, motors and gears.
AEGs are popular because they can shoot full-auto, which gamers and collectors both enjoy. They also are among the fastest-shooting airsoft guns, although bolt-action sniper guns can be modified to be very fast, as well. AEGs allow people to experience things that most people cannot experience with firearms; and, of course, they do it at a fraction of the cost. Even law enforcement agencies are using AEGs as training simulators because they’re much safer than firearms that shoot training ammunition called Simunitions. You can make a mistake with a firearm and kill someone — it happens all the time. But you can’t possibly load a firearm cartridge into an airsoft gun, no matter how realistic it may seem.
The technology is changing rapidly. Today, there are even a few hybrid AEGs that can be used with or without electrical power. Obviously, these will appeal to people who never want to be caught without a functional gun.
What comes next?
Next time, I’ll talk about modifying airsoft guns. Not all guns can be modified, but a surprising number can be; and the manufactures do supply the parts to make the modifications.
I’ll also talk about power, which is fast becoming an important topic. As the guns become more powerful, the “soft” in airsoft is being tested to the limits.
by Tom Gaylord, a.k.a. B.B. Pelletier
The Chinese Fast Deer sidelever air rifle is attractive. Does its performance live up to its looks?
It’s been a long time since we looked at the Fast Deer sidelever. The last report was in December of last year! At that time, I was unsatisfied with the results of the 25-yard targets because of how well the rifle seemed to do at 10 meters. I said we might come back to it, but the gun got put on the back burner to simmer while I did other things.
It was those other things that bring you today’s report, and surely the ones that must follow. I’ve spent a lot of time this year exploring the fundamentals of airgun accuracy. Of course, I’ve barely scratched the surface, but some of the things that have popped up have been surprisingly helpful in ways I couldn’t imagine when they happened. One of them was the test of the Diana model 25 smoothbore that we finished way back in March of this year. In Part 4 of that test, I saw that while the smoothbore was very accurate at 10 meters, it was pretty bad at 25 yards. From those results, I deduced that spin is important to stabilizing a pellet over longer distances, while the high drag of the diabolo pellet is sufficient for accuracy at close range.
It wasn’t until I wrote a column about the Fast Deer for Shotgun News this month that I noticed the Fast Deer’s 25-yard targets resembled those of the Diana 25 smoothbore more than a little. The Fast Deer was also accurate at 10 meters but not at 25 yards. So, here was a rifled bore that performed like a smoothbore. Could we learn something from this? Is the Fast Deer capable of better accuracy than we saw in Part 4?
I was so impressed by these results that I wrote a special report titled Advanced airgun diagnostics: Part 1, in which I showed you the comparison between the 2 airguns. Yesterday I tested the Fast Deer again at 25 yards, but this time I did so believing that it was the fault of the pellet that made the groups so large. Turns out I was only partly correct, and therein lies the meat of today’s report.
I had one pellet that fit the Fast Deer’s bore well…both the skirt and the head. It’s a Tech Force domed pellet that Pyramyd Air used to sell but no longer does. That makes it a Chinese pellet, and I’ve seen only one other Chinese pellet that was worth a darn. That one was a hand-sorted wadcutter that I used to compete with in 10-meter pistol.
These Tech Force domed pellets are larger than most. They fit the bore of the Fast Deer rifle well.
The subject pellet fits the bore well, but not tight. Many other pellets just fall out of the breech, indicating a too-large bore, which is characteristic of Chinese air rifle barrels. I knew from the last test that the rifle was at least on paper at 25 yards, so I set up at 25 yards indoors and commenced firing. The first 10 pellets all landed to the right of the aim point, but they were all on paper, so I finished the first 10-shot group with the sights set where they were. This group measures 1.428 inches between centers. That’s not great, BUT — it’s actually smaller than the best group I had fired in the entire last report! In that session, the best group was shot with Air Arms Falcon pellets, so I knew I had to try them again for comparison; for now, I stayed with these Chinese domes.
Ten pellets made this first 1.428-inch group. It may not look good, but this is the best 25-yard group this rifle has made so far.
After the first group was completed I adjusted the rear sight to the left. You may remember that I had flipped the sight backwards in response to a suggestion blog reader Vince gave me. That gives a sharper rear notch when aiming, and any little thing like that will help. So, all adjustment had to be done backwards; but since this sight has a very visible index mark to watch, the adjustment was no problem.
As I adjusted the sight, I also discovered that the entire unit is loose. It’s mounted on the gun securely enough, but the very construction of the sight itself is a sheetmetal tangle of parts that will always be loose and subject to movement.
The rear sight is clearly marked and easy to adjust, but it’s always going to be loose because of how it’s made.
I decided that I had to push the sight to the left before every shot. That would hopefully return it to the same place every time, giving me the best chance to get good results from it despite its looseness. Then, I shot the next group with more Chinese domes. I forgot to move the sight for 2 of the 10 shots. Nevertheless, this group measures 1.328 inches between centers, which is a significant improvement.
Ten shots went into 1.328 inches at 25 yards. I never thought I’d be happy with a group like this, but I am! It’s interesting that perhaps 6 of the pellets in this group went into a much smaller cluster near the center of the main group.
After this target, I adjusted the rear sight once more and then shot a third 10-shot group with the Chinese pellets. I only forgot to push the sight once this time, on shot 9. The group measures 1.597 inches between centers, which is the largest group shot this day with this pellet. Perhaps I was tiring?
Ten shots went into 1.597 inches at 25 yards. I never thought I would be happy with a group like this, but I am! While it’s tempting to think that the shot on the left was the one that I didn’t push the rear sight for, I cannot say that for certain.
It was time to try the Falcon pellets again. In the last test, 10 Falcons made a group that measured 1.497 inches between centers at 25 yards. This time, 10 went into 1.783 inches. Obviously that’s a lot larger; but if you examine the group, you’ll see that 7 of the pellets went into just 0.692 inches. Taking that and the other group-within-a-group that I shot with the Chinese domes, I came to the conclusion that this Fast Deer may really be accurate but is being hindered by its open sights. The next test of this rifle must therefore have a scope mounted.
I do not like testing airguns that have been given every chance and still haven’t performed. Every once in awhile, something anomalous like this Fast Deer jumps out at me and needs to be investigated further. If it hadn’t been for my going over the results of this rifle so close to the time I reported similar results from the Diana 25 smoothbore, I might never have given this rifle its second chance today. Now, we’ll all get to see if that was worth it.
I admitted up front that this test demonstrated that the pellet was only part of the reason the Fast Deer has been inaccurate at 25 yards. From today’s test, we might conclude that the poor rear sight that moves is also affecting the outcome. In the next test, I need to make sure that the scope is locked down solid, so the rifle is free to be as good as it can be.
by Tom Gaylord, a.k.a. B.B. Pelletier
Remember that I said I would return and do another accuracy test of the Beeman HW 70A pistol because I didn’t test the best pellet seated? I felt a little guilty about missing that; but after my wife, Edith, got done with me, I felt really guilty. Good job, Edith!
Today is a revisit to see the effects of deep-seating the best pellet, which you may recall was the Beeman H&N Match. The other two pellets I shot last time aren’t in the running, so they don’t get retested.
However, a reader commented that his HW 70A really likes the JSB Exact RS dome, so that one got tested, too.
Several readers described their pistols as very accurate. One person even said his was a tackdriver. That really drives me nuts because of the results I’m getting. And I’m a good pistol shot — plus, I’m shooting the gun rested! I ought to be there with the best of you, but up to this point I’m not.
Beeman H&N Match
This was the best pellet in the first accuracy test, so this is the one I started with. And I started with the deep-seated pellets. I’m using the Air Venturi Pellet Pen and Seater, and the adjustment hasn’t changed since the last time, so everything is equal.
The first group was pretty poor. I thought I’d forgotten how to shoot because it looked nothing like the group of flush-seated pellets from the last time.
That prompted me to try a group of the same pellets seated flush. You will remember in Part 3 that, when these were seated flush, 10 of them made a 1.085-inch group. This time 10 flush pellets went into 1.067 inches. That’s pretty close to the last time, and very persuasive that flush-seating is what this pellet likes!
JSB Exact RS
Next I tried some JSB Exact RS domes — just to see if I could duplicate what a blog reader reported. Lo and behold, I did! As I was shooting, I could see that the group didn’t seems to be growing, and I had a sense that the pistol was drilling the target. As you can see, it was doing exactly that! Ten pellets in 0.761 inches at 10 meters. I wouldn’t call it a tackdriver, but it’s the next best thing.
Next, I was going to try the same pellet seated deep, but that’s when I saw that the barrel was flopping from side to side at the breech! Oh, no! All that work for nothing!
Fortunately, this pistol has a pivot bolt that can be both tightened and also locked in position with a jam screw. However, I didn’t have time to do that because I was crashing on tests to put in the bank for my trip to see my friend Mac.
When I return from my trip, I’ll tighten the breech and rerun this entire test — plus shoot the RS pellet deep-seated. So, there’s fifth part coming.