Posts Tagged ‘air pistols’
Smith & Wesson 586 pellet revolver: Part 2
by B.B. Pelletier
Smith & Wesson 586 pellet revolver is a classic for airgunners who like shooting pellet pistols.
Let’s look at the velocity of our Smith & Wesson 586 with the 6-inch barrel. But before I get to that, let’s first look at the trigger-pull.
Here’s the revolver with the cylinder open. It’s easier to remove the circular clip from the crane and load it separately than to load it while it’s still in the gun like this.
This test gun has the most variable trigger I’ve tested recently. In the double-action mode, it breaks between 8 lbs., 10 oz. and 9 lbs., 6 oz. In single-action mode, it broke somewhere between 5 lbs., 1 oz. and 6 lbs., 10 oz. That’s a broad range in either mode, yet when I hold the gun and pull the trigger normally I can’t feel the difference. So forget what the numbers say — the trigger feels remarkably stable and even light!
Velocity
I tested the gun with three pellets. Each was tested in both the single-action and double-action modes because you get different velocities in each mode in some guns.
Crosman Premier 7.9-grain
The Crosman Premier Lite averaged 390 f.p.s. in the single-action mode. The spread was large, ranging from 377 f.p.s. to 416 f.p.s. That’s a total spread of 38 f.p.s. All shooting was done with at least a 10-second pause between shots, and the temperature in the room was 70 deg. F.
The same pellet in the double-action mode averaged 389 f.p.s., so not much difference. The range was from 372 to 403 f.p.s., for a spread of 31 f.p.s. Taking 390 as the average, Premier Lites generated 2.67 foot-pounds at the muzzle.
Air Arms Falcon
The Air Arms Falcon pellet was next. In single-action, it averaged 406 f.p.s., with a 24 f.p.s. spread from 398 to 422 f.p.s. In double-action mode, this lightweight domed pellet averaged 398 f.p.s. with a spread from 376 to 425. That’s 49 f.p.s. between the fastest and slowest. At a velocity of 402 f.p.s., the Falcon generates 2.62 foot-pounds of energy. I selected a velocity that falls between the averages of the single-action and double-action modes.
RWS Hobby
The 7-grain RWS Hobby pellet is still the one I use to test maximum velocity in most airguns. In this revolver, the single-action mode gives an average 428 f.p.s. The spread ranges from 414 to 441 f.p.s., for a difference of 27 f.p.s. In double-action, the revolver averages 411 f.p.s. with Hobbys, and the spread goes from 391 to 422 f.p.s. That’s a spread of 33 f.p.s. At 420 f.p.s. the Hobby generates 2.74 foot-pounds of energy.
How many shots on a CO2 cartridge?
I got 40 powerful shots before the velocity began to decline. From 41 to 50, it declined in a straight line, starting at 377 f.p.s, and ending at 292 f.p.s. That would be where I would stop, so for casual shooting I’d say it gets 50 good shots on a CO2 cartridge. The danger of shooting more pellets in a CO2 gun when the velocity begins to drop off like this is that you’ll eventually get one stuck in the barrel. If you quit while you’re ahead, that won’t happen. Fifty shots is standard for air pistols of this power.
What have we learned?
This test was interesting because it showed there’s a slight advantage in velocity in the single-action mode. The description says the gun gets 425 f.p.s., and the results seem to agree with that number. It also shows that this pistol has a wider velocity spread than most CO2 guns. It demonstrates that you cannot judge a gun only by numbers, since the trigger-pull figures are high, yet the trigger-pull seems both light and crisp in both modes.
So far, I have to say this S&W is every bit the wonderful airgun that I remember. Can’t wait to see how accurate it is.
The spring-piston powerplant
by B.B.Pelletier
Today, I’m going to do a fundamental report that I promised some time back. I’ll show you how a spring-piston powerplant works. I’ll also show you how to measure mainsprings so you can find replacements when yours wears out. We had a question yesterday morning from a blog reader named Peter:
Hi Tom! Been trying to locate a replacement spring online for about the last six months. What I have is a pre-war Diana model 45 underlever. I have read on different blogs that springs from other guns can be used; but when contacting these spring suppliers, they say that if it’s not in their online catolog it’s not available. At any rate, there must be someone, somewhere that would be willing to sell a spring that would work in this gun. What baffles me most is there must be hundreds of other people who have located springs for their old airguns, but in six months of searching have had no luck in locating their source. Tom, I need your help before I go completely bazonkoos!!!
Well there’s not much chance of a pre-war Diana airgun mainspring being available anymore, is there? World War II ended in 1945, which was 67 years ago, and the chances of finding a new old-stock mainspring are virtually impossible. However, all is not lost. There are plenty of mainsprings around today that can be made to work. All you have to do is measure the old spring, so you know what’s needed. I’ll come back to this, but first I want to discuss how the spring-piston powerplant works.
The spring-piston powerplant
There are a number of ways they can work, but the basics of the spring-piston powerplant is a spring pushing a piston that compresses air that then pushes the pellet. That’s it in a nutshell. There are no valves or moving parts, other than the piston and mainspring. The air is compressed ahead of the piston in a part of the spring tube called the compression chamber.
In the end of the compression chamber, there’s a hole called the air transfer port. It’s where the compressed air leaves the compression chamber and gets behind the pellet, because the breech is in line with the transfer port.
This side view of two air transfer ports shows how they work with the piston to channel high-pressure air behind the pellet. The port may be offset compared to where the breech is located in relation to the compression chamber.
This drawing shows how the pellet seals the end of the compression chamber, which is on the right in this view. The compressed air has nowhere to go, other than behind the pellet.
This Beeman R1 rifle has a special replaceable transfer port installed. That’s the reason the Allen screw is on top of the spring tube. But the transfer port here looks like most breakbarrel transfer ports.
When a spring gun is fired
Most spring guns, including those with gas springs, work the way I’m about to describe. When the gun is cocked, the mainspring is compressed by the piston, which is held in the rearward position by the sear. When the trigger releases the sear, the piston springs forward, compressing air as it goes. When the air is fully compressed it stops the piston before it hits the end of the compression chamber.
On some guns that aren’t properly designed or guns that have been tuned incorrectly, the piston actually slams into the end of the compression chamber because the air pressure isn’t high enough to stop it. This is why some pellets feel much harsher than others in a spring gun — because they either move too soon and are unbalancing the powerplant (allowing things to happen that shouldn’t) or they remain in place too long, allowing the piston to rebound off the high-pressure air in the compression chamber.
The powerplant
This is the question that started this report. A reader asked me to show what a spring-piston powerplant looks like. This is it, except for the outer spring tube.
These are the major parts of a spring-piston powerplant. They fit inside the spring tube and the mainspring fits inside the hollow piston. It also fits over the spring guide, which is shown in front of the trigger. Some guns also have a shorter spring guide at the front of the spring that fits inside the piston. Because of its shape, it’s called a top hat — shown above the end of the spring.
The piston is hollow, as you can see here. The mainspring fits between the central rod, which is used to engage the sear and the inside of the piston. The better the fit here the less the gun will buzz. A tin soda can could be cut to make a liner to fit inside the piston and take up any slack between the mainspring and the piston.
Here you see the piston in the cocked position. The trigger has caught the piston and will hold it in place until the trigger is pulled. The spring guide is not shown here so you can see this relationship, but it would be against the front of the trigger and extending into the hollow piston, inside the spring. The piston rod that you can see passes through the spring guide.
How to measure a mainspring
Pete asked where to get a mainspring for his pre-war air rifle. I told him he’ll have to get one that is close and make it work, Let’s take a look at what that means.
There are several measurements you need to know when measuring mainsprings. One is how fat the spring is on the outside, so you can determine if it will fit inside a piston. Be careful with this one, though, as springs will buckle when they’re compressed and become wider than they measure at rest. Always allow yourself some wiggle room until you get the hang of it.
The second measurement is the inside diameter of the spring. It has to fit over the outside of the spring guide and top hat, if there is one. You want the fit of the spring over the rear spring guide to be very tight or “nailed on” as Jim Maccari says. The spring will get a trifle wider when it’s compressed, so don’t worry if it’s very tight — as long as it fits over the guide.
Lastly, you need to know how long the mainspring will be when it’s fully compressed. That helps determine if you’ll be able to cock the gun or the spring will become coil-bound before the sear grabs the piston. Look at the picture of the piston in the cocked position above. The compressed mainspring has to fit in the space provided when the piston is in that position and the spring guide is in place.
This graphic tells you how to calculate the compressed length of a mainspring.
What if the spring is too long?
You can live with a spring that’s too long, as long as all the other measurements work. When the spring is too long, you cut off some coils to make it fit. I use a Dremel tool with a cutoff wheel for this, and I cut with the wheel at 90 degrees to the axis of the spring wire. Then, if I want a beveled end, I can grind the end of the spring on a bench grinder to get it flat again.
I don’t bother to collapse the last coils of the spring the way they come from the factory, but if I wanted to I would heat them red hot and whack them with a hammer until they bunch up. I would have to use heat-sink paste or a good wet towel above the spot where the spring was heated to prevent more of the spring wire from softening this way. Then I would quench the job in water when it was completed. But like I said, I don’t bother doing that and my springs seem to work fine.
Where to get mainsprings
Now that you know how to measure a mainspring, you probably want to know where to buy them. I know of three possible sources. First is Pyramyd Air, which sells many replacement springs for current and obsolete models. Some of the old Weihrauch, FWB and Diana mainsprings can be modified to fit many older airguns. The HW55 mainspring and the FWB 124 mainspring are both quite long and can be cut to fit many other guns.
The second source is John Groenewold, of JG Airguns. Contact him at http://www.jgairguns.biz. John buys vintage parts in the UK for many old classic airguns and often has parts for those oddball guns. He may even know if he has a spring that will work for you, even if it isn’t commonly listed anywhere.
Third and perhaps the best of all is Jim Maccari, also known as the Springman. Visit his website at http://www.airrifleheadquarters.com. Jim makes springs for many older airguns, plus he can sometimes find a spring that will serve for something other than what it was made for.
Smith & Wesson 586 pellet revolver: Part 1
by B.B. Pelletier
Smith & Wesson 586 pellet revolver is a classic for airgunners who like shooting pellet pistols.
I’m starting a report on a classic air pistol. It’s one that is so well designed that it has caused a stir in the firearms community. I’m looking at Smith & Wesson’s 586 revolver. The 586 exists in S&W’s line as a .357 Magnum revolver, along with its stainless cousin, the 686. The pellet gun also comes in both black and silver finishes, and the silver finish is named the 686, just like the firearm. Both guns are .177-caliber pellet guns with rifled barrels. No other calibers are available.
A barrel/shroud wrench still comes packed with each revolver, and these guns offered replacement barrels of different lengths at one time. I’m testing the gun with the 6-inch barrel, but a 4-inch barrel model is also available. Spare barrels are now available only on the used gun market.
This pellet gun is a true revolver, with a rotating metal clip that mimics the cylinder of a firearm. The clip is only a little longer than a pellet and sits at the front of what appears to be a full-sized cylinder. But when the crane swings out, only the clip comes out of the gun. It then lifts off the crane for loading. The gun comes with a second clip, and each clip holds 10 pellets. All clips are black, so they look out of place on the silver gun.
The thin, metal circular clip swings out to the left like a revolver cylinder.
I’ve reviewed this gun before on this blog. Most recently, I looked at it in a 2-part report in 2008. But things have changed since I last tested this air pistol, and I wanted to update the information. If you’re serious about wanting a fine air pistol that’s affordable, this is one of the few to consider.
The biggest change to the gun I’m now testing is the finish that has gone from shiny to matte black. Pyramyd Air photos show the new finish very clearly; but if you weren’t aware of the change, you might miss it. I note that the 4-inch barrel model is currently shown on the website with the shiny finish. Maybe there are still some older guns in the system, because in the new Umarex catalog both guns have a matte finish. Edith is looking into this for us.
The gun comes with several accessories packed in the box. There are front sight blades, a spare circular clip, the barrel wrench and a bore-cleaning brush. The owner’s manual is clearly written and very detailed.
These accessories come in the box with the gun, except one of the circular clips is installed in the gun. The barrel wrench is not shown here.
Sights
The gun comes with three front sight posts of different widths to suit your personal preferences. Heck — even Smith & Wesson doesn’t do that with their firearm revolvers! Each insert can be quickly installed with just a single screw. Different width front posts are meant to suit shooters who have eyes of different focusing ability. Generally speaking, you want the widest front post that still allows light to show on either side in the rear notch. That makes aiming at black bullseyes much easier.
The rear sight is adjustable in both directions. Surprisingly, no screwdriver is included with the gun. I say that because every S&W revolver I ever bought had a silver-handled screwdriver for this purpose. I felt no crisp detents on either adjustment, but the vertical screw does pause as it turns. The horizontal screw just turns smoothly, as far as I can tell.
Action
The 586 is both single- and double-action with really great trigger-pulls in both modes. I’ll measure the trigger and comment more in Part 2, but you can rest assured this revolver’s trigger is one of the best things about the whole gun.
Weight
The .177-caliber pellet gun weighs 45.4 ozs. The .357 Magnum revolver of the same barrel length weighs 46.3 ounces. That’s pretty close! I’ve owned a 686 .357 Mag and can tell you this gun feels like the real deal!
Where does the CO2 go?
There’s only one place for the CO2 cartridge to go, and that’s inside the grip. Flip down the bottom of the grip that also serves as the CO2 cartridge piercing lever. That gives you access to the underside of the right grip panel, which then flips off with ease. Inside is a standard CO2 cartridge adjustment mechanism that allows cartridges of slightly different lengths to seal properly.
The right grip panel comes off to access the CO2 cartridge compartment.
Nice box!
The revolver comes packed in a nice hard case with foam lining. Each accessory has cutouts at the right spot, so nothing slides around. It’s the same way firearms come these days.
The revolver comes in the same kind of box as a firearm.
Overall opinion
I guess I’m attracted to this revolver, because this will be the third time I’ve tested it for you. It’s a classic that has a great trigger, many useful accessories and, hopefully, the accuracy we have come to expect from Smith & Wesson. Though they don’t actually make the gun, they do license their brand on it and are very interested that it is perceived as a good handgun. I think it is, and I hope to show that to you in this test.
It’s a pretty gun.
Learning to shoot with open sights: Part 4
by B.B. Pelletier
This series began with the earliest sights that were both primitive and simplistic. Then, we looked at the evolution of peep sights, starting back before 1840 and progressing to around 1903.
There’s a lot more to be said about both open and peep sights. It was at this point in time that they each began to develop along separate lines. I think I need to concentrate on one type of sight per report to keep things straight. In today’s report, I’ll look at open sights from around the middle of the 19th century until today.
Open sights evolved rapidly after the American Civil War, which ended in 1865. Not that all the innovation was done in the U.S., mind you, but that was a time when the world of firearms was advancing though technological stages, and the sights kept pace with everything. Other wars around the world at the same time drove the armies of many nations to push the limits of firearms; and we got smokeless gunpowder, fixed cartridges, breechloading arms and eventually repeating firearms from this era.
In 1850, a military firearm was loaded at the muzzle and carried but one shot. Repeaters at this time were novelties and even dangerous experiments because of the volatility of black powder. These single-shot martial arms were accurate to about 400 yards on man-sized targets.
In 1900, there were repeating firearms holding 10 self-contained cartridges filled with smokeless powder and spitzer (pointed) bullets that could shoot accurately to more than one mile distance. Most of the primary designs we use today had been invented.
I stopped discussing open sights when I started my look at peep sights; but even though the advances in open sights were not as great in terms of the improvements they contributed to accuracy, open sights did advance in parallel with peep sights.
Range-driven improvements
The old black powder arms were accurate; but because they shot their bullets so slowly, the trajectories were huge. Bullets dropped by many feet on their way to the target. We all like watching Matthew Quigley shoot his big Sharps rifle at distant targets, but how many people appreciate that his bullets are dropping by 60-80 FEET before they impact the target?
Enough fantasy. Let’s get real for a moment. In 1874, the U.S. and Irish rifle teams shot a match at the Creedmoor range on Long Island to decide which nation had the world champion marksmen. They shot at targets at 800, 900 and 1,000 yards. At 1,000 yards, the bullets from the Americans’ .45-caliber rifles dropped more than 100 feet. So, they had to set their sights to compensate for this tremendous drop. A 550-grain .45-caliber lead bullet starting out at 1,400 f.p.s. will drop 114.69 feet when it gets to 1,000 yards.
This model 1873 Springfield Trapdoor carbine rear sight (from 1878) is graduated to 500 yards on the ramp and to 1,100 yards on the upright standard. There’s another sight at the top of the standard that’s sighted even farther — perhaps 1,300 yards. Image copied from Trapdoor Springfield by M.D. (Bud) White and B.D. Ernst, copyright 1980, Beinfeld Publishing, Inc.
This 1879 Remington rolling block rear sight on an Argentine military rifle chambered for .43 Spanish (11.15 x 58R) is elevated to shoot 400 yards. By flipping the standard straight up, the rifle can shoot out to 900 yards accurately.
I mention this because airgunners everywhere are so willing to condemn the .22-caliber pellet for having a “rainbow trajectory.” Folks, they don’t know the meaning of that term! And this is the reason that I refuse to give up my fascination for firearms — because I often find remarkable parallels between them and airguns. But some shooters will watch Quigley and then opt for the fastest .177 they can buy, so their pellets don’t drop too much at long range! To heck with that! Instead, take the time to learn where the pellets will drop and shoot the more accurate, heavier pellets. That’s what Quigley did.
So, the military rear sights of the 1870s were long affairs that had inclined ramps to raise them up for long-range shots. By 1900, this had been taken to the absurd limits of 2,000-yards. Nobody could see that far on the battlefield to shoot accurately; but by this time, military leaders were espousing area fire and talked about “beaten zones” and “cones of fire.” They were thinking of rifle bullets in a way similar to artillery shells, except they didn’t explode, of course.
By the turn of the 20th century, military leaders were thinking in terms of 2,000 yards and indirect plunging fire, as this 1896 Mauser rear sight shows. Image copied from Mauser Bolt Rifle, Third Edition by Ludwig Olson, copyright 1976, E. Brownell & Son.
By the time World War I started, the theory of indirect rifle fire was at its height, though it was proven ineffective through actual battlefield experience. Soldiers were also trained to shoot at targets directly, which ended up being the direction that proved the most effective. But the theory did not die. It persisted until the start of World War II, and the weapons that were used continued to have rear sights that adjusted for 2,000-yard fire.
Countries were also experimenting with ammunition at this same time (1898-1915). As each new innovation hit the field, nations scrambled to adapt their weapons to more modern designs that shot farther and flatter. As a result of what they learned, the rear sights also changed to reflect the flatter trajectories.
This model 1898 Mauser rear sight has been updated to reflect the more streamlined 8mm ammunition used during World War II. It’s shown elevated for 2,000 yards, but looks just a little higher than the rolling block rear sight of 1879 that’s set for 400 yards.
Of course, civilian arms kept pace with the military weapons in every way. Once the wars were over, the sights on civilian arms gained the same innovations that served the military so well; because they were sold to individuals instead of governments, they had to be more practical. No shooters wanted sights that were good for 2,000 yards — no matter what their military experience had been. So, the rear sights still elevated, but this time to more reasonable yardages.
This Winchester model 94 rear sight is probably good out to 200 yards, or so (for the 30-30 round). Photo copied from Winchester Model 94 by Robert C. Renneberg, copyright 2009, Krause Publications, Inc.
And I would be remiss if I didn’t mention the express sights that were popularized by African hunters from the 1870s through the 1920s. These are sights that flip up and are regulated for a single cartridge at a single range. The most common that I have seen are those for 100, 200 and 300 yards — but there are many other combinations.
Winchester express rear sight has three flip-up blades for distances to 400 yards. Image copied from Winchester — An American Legend by R.L. Wilson, copyright 1991 by R.L.Wilson. Published in U.S.A. by Random House.
The express sight is a special adaptation of the earlier leaf rear sight that has two distances built in. Those go back as far as the 1850s. I showed you one on my 1867 gallery dart gun.
This rear sight from a gallery dart gun of 1867 could have been the inspiration for the express sights.
Well, that’s it for this time. There’s much more to say about open sights — mainly on the civilian side. We need to look at them, because airgun sights are directly related.
We’ll also look further at peep sights because we haven’t exhausted them, either. This series has at least a couple more parts to come.
Some scope fundamentals: Part 2
by B.B. Pelletier
This is one of the most popular reports I’ve done in a long time. That may be because scopes can be very cantankerous to deal with — hard to mount, difficult to zero, always seem to shift their zero, etc. Today, I’ll address some of the problems you can have and some ways to minimize them.
Scopes should work — no?
To the non-shooter, the telescopic sight seems like a guarantee of accuracy. We’ve all seen the movies. Put the crosshairs on the target, squeeze the trigger and you can’t miss.
Then, you try it for the first time, and you notice that you can’t keep the scope’s reticle (crosshairs) steady. As long as you hold the rifle, no matter what you do, the crosshairs move. Each beat of your heart makes them jump a little. Each breath you take in can move the scope or at least tilt it. You can minimize these movements through training, but nobody can eliminate them entirely. That’s why I shoot from a rest so often. But sometimes that doesn’t work — especially with spring-piston airguns. You have to learn the artillery hold; and since that technique goes well beyond what many people think, I’ll explain it more fully here.
Relax for a neutral hold
The artillery hold is really just a way to get you to follow through, but there’s more to it. An important part of the hold is how you are at the instant the gun fires. You have to be completely relaxed, so the gun doesn’t recoil back and encounter an off-center obstruction that shifts the muzzle in a certain direction.
Here’s how to achieve this relaxed state. After putting the crosshairs on your target, take a breath and expel most of it. Try to relax as you do this. The crosshairs will usually move off the target in a certain direction. If you had fired before relaxing, the pellet would have gone off target in the same direction the crosshairs just did. Maybe it wouldn’t have gone quite as far as the crosshairs seemed to, but it would have moved in the same direction. The result is a larger group.
Let’s try again. This time, after you relax, move the crosshairs back on target by shifting the gun or your hands slightly. It doesn’t take much.
Once you’re back on target, take a deep breath, close your eyes, let out most of the air and relax again. Now, open your eyes and see where the crosshairs are. They probably moved again, only this time they didn’t move so far. Shift things to get back on target again and repeat this procedure.
You may have to repeat this procedure several times before the crosshairs are still on target when you open your eyes. When they are, you can take the shot — making sure that you allow the gun to recoil and move as much as it wants to. This time, the shot should feel very different than it normally does. It should feel neutral — as though you’re no longer connected to the gun. That’s the feeling of a perfectly neutral shot and one that will group as tightly as the gun is capable of — if you can repeat the process several times.
What does this have to do with scopes? Everything! This is the only way to shoot a recoiling airgun with any accuracy; and until you can do that, you’ll never have much success with a scope.
With most firearms, except .22 rimfires, the hold isn’t nearly as important for accuracy because the bullet is out of the gun before all the movement takes place. But with airguns, and especially spring-piston airguns, the pellet hasn’t started to move before the gun does. Only a .22 rimfire is similar, and even they’re much more forgiving than most airguns.
However, you do need to know that all firearms are affected by hold, as well. Even centerfires that shoot in excess of 3,000 f.p.s. will benefit from the hold I’ve described here, but the amount of accuracy increase is so small that it’s only of interest to target shooters and long-range varmint hunters. The average shooter won’t normally notice the difference between a 1-inch group and a 1.25-inch group at 100 yards. Or if they do, they won’t care. I’ve heard that from so many shooters at my rifle range over the years that I know it’s true.
Now you’re ready
If you can learn how to neutralize your rested hold using the process I just described, you’ll see an immediate increase in accuracy from your scoped guns. Then, you’re ready to discuss scope fundamentals!
Temperature is critical
We don’t appreciate how sensitive a modern telescopic sight can be. I don’t mean fragile, either — I mean sensitive. Every change in temperature changes the point of impact of your scope a little. No scope is immune to this phenomenon, yet most shooters act as if once the scope is zeroed it stays zeroed.
Field target shooters know different. I’ve seen a field target scope with three different sets of click values on the elevation knob, each color-coded to a 20-degree temperature range. The shooter who owned that scope took the time to not only figure out all the elevation click values for every yard between 10 and 55 — he did it three separate times when the temperature was in three different ranges! That’s something Hollywood will never show you.
The optical elements inside a scope are refracting light to the millionths of an inch. When they move in relation to one another — because the metal tubes that hold them expand and contract from changes in temperature, the light beams do move. The movement is very slight, but it can and sometimes does change where the images appear. The point of aim changes.
There are many other reasons for a shift in the point of aim, but temperature is a constant one that must always be taken into account. If you’re looking for the way to prevent such changes, I’m sorry to disappoint you. There’s no solution to cancel the effect of temperature changes on a telescopic sight. But if you know it will happen you can at least anticipate it and adjust your scope when the time comes.
Reticles
There are so many different kinds of scope reticles that it would take a book to cover them all. And most of the highly specialized ones are for specific purposes, such as the ballistics of a single military round, so they have no place in a general discussion. I’ll address hree general types of reticles found on most scopes. If I miss something, you can bring it up in the comments.
The oldest type of reticle is the plain “crosshair,” which is two straight lines — one vertical and the other horizontal. In some scopes, these lines actually appear to move as the scope is adjusted, but that’s getting pretty rare today. More often, the crosshairs remain in place in the center of the image and the adjustments move the whole image, so you don’t notice anything.
The plain crosshair is the oldest type of reticle. This image shows thick reticle lines, but they can be much thinner for greater aiming precision.
Often a very thin reticle can be difficult to see against a background, so there will be a small dot at the center of the crosshairs that makes them stand out. This dot will be small, perhaps one or two minutes of angle (a minute of angle covers about one inch at 100 yards), but it doesn’t take much to be noticeable against anything but a dark woods background.
This dot looks large on the heavy reticle lines. But in many scopes, both the dot and reticle lines are very small and fine. This is just for illustration.
Plain crosshairs are best in open country and are therefore favored by long-range shooters. They’re fine for plinking, as long as the reticle lines aren’t too thin. They’re less useful in deep forests, where the reticle lines don’t stand out. For that terrain, probably nothing beats the duplex reticle.
The duplex reticle is a plain crosshair that has thicker lines near the edges of the field of view and thinner lines in the center. When I shot field target, I used a scope with a duplex reticle for two reasons. First, it was much easier to see in the deep woods where many matches are shot; and second, the duplex offers four additional aimpoints.
The duplex reticle uses crosshairs of two different sizes. The ends of the thick posts provide four additional aim points that can be used for things…like greater or lesser distance and wind.
Duplex reticles are the favorite of hunters, because they work well in deep foliage yet they permit precise aiming at the same time. Like plain crosshairs, duplex reticles come in different thicknesses.
In the mil-dot scope, the dots are an exact size (measured in mils) and are spaced apart an exact distance. On variable scopes, they must be used at one power setting to work as designed. Read the information that comes with the scope to discover how this works.
Mil-dot reticles are a more recent invention. They feature dots of a controlled size spaced along one or both reticles at regular spaces. Mil is short for milliradian, a measure of angle that, unfortunately, has never been standardized. Or perhaps it’s more correct to say that it has been standardized dozens of times — each with a different measurement. When I was a mortar platoon leader, our fire direction center and mortar sights used the old French measurement of 6,400 mils to a circle, but there are many other measurements that differ — some slightly and others in a more significant way.
One common use for the mil is rangefinding. Though it isn’t exact, we say that one mil subtends (covers) one meter at 1,000 meters. At 100 meters one mil subtends one-tenth of a meter or 3.9 inches. That’s so close to 4 inches that we round it up.
A whitetail deer is about 12 inches from the top of the shoulder to the bottom of the chest. A two-mil dot will just about cover the deer’s chest at 150 meters.
Is that too much for you? It is for many hunters who still use the mil-dot scope for aimoff when there’s wind. Or they use the vertical dots for aim points at distances other than the range for which the scope is sighted.
Focusing the reticle
The first thing a shooter must do with a scope is focus the reticle. The eyepiece should adjust to allow you to do this, and it does on all but the cheapest scopes. Focus by looking through the scope at the sky or a light-colored wall and turn the eyepiece until the reticle appears in sharp focus. I’ve read that this is supposed to be done incrementally; because if you stare at the reticle very long, your eyes will naturally focus on it. So do it in stages.
After you focus the reticle, some scopes have a locking ring to hold that focus. Others don’t have the locking feature, but the focus rings should be stiff enough to hold your focus without it.
Focusing the reticle is very important for scopes with adjustable objectives, because the scope’s designers assume the scope is in sharp focus when the objective ring or sidewheel is turned. Only when the reticle is in focus will the scope come close to the distances marked off on the parallax ring or knob, which is the adjustable objective we are discussing. And, of course, that will also depend on the temperature when the scope is used.
On the other hand, on lower-powered scopes that have a fixed parallax setting you can use the focus to bring close targets into better focus. This isn’t what the adjustment is for and it will blur the reticle somewhat, but sometimes it’s the best way to use a low-priced, fixed-focus scope at closer distances than it’s intended.
Some scope fundamentals: Part 1
by B.B. Pelletier
I’ve noticed that a lot of you are responding positively to the fundamentals that have come out in some of the recent reports, so I thought I would do a few more important ones for you, starting with scopes. This will be a series of bite-sized reports.
My experience shooting the Conquest with a 4x scope at 50 yards last week and getting great groups prompts me to want to share a number of scope evaluation tips with you. And, as always, I expect the comments from our readers are going to be even more interesting than the reports.
What magnification (power) to choose?
Starting with the Conquest accuracy test, it’s obvious that you don’t need a lot of magnification to shoot well. I normally use more than just 4x for a gun as accurate as the Conquest, but not on all rifles. As a scope increases in power, it also gets longer and heavier, so a compromise between power and size is usually best.
I have some 3-9x scopes that have unusually clear optics and thin reticles that I enjoy using. Of all of them, the one I like the best is not marked in any way. I think it’s a Leapers, but there are no identifying marks that reveal who the manufacturer is. The optics are clear and the crosshair is thin and sharp. This is often my go-to scope to use for a quick test.
My favorite power combination is probably a 4-16x. I find it packs the most power into a convenient package without the scope becoming too long and heavy. Given today’s optics, a good 4-16x isn’t much longer than a 3-9x from a decade ago.
But you don’t need even 16x to shoot accurately. That is what the new airgunner must understand. I have a .250 Savage centerfire rifle that shoots 10-shot groups smaller than one inch at 100 yards nearly every time. The scope on that rifle is a vintage all-steel Weaver V9 W, which means it is a 3-9x variable that has a wide field of view. The objective lens is only 32mm, so it isn’t as bright as some modern scopes, but it has a super-fine reticle with a tiny dot at the intersection of the crosshairs. If I ever find another scope like this at a gun show, I am prepared to buy it because the combination of power, optical clarity and crosshair size is ideal for this rifle. I use this rifle for prairie dog-sized targets out to 300 yards. That’s good enough for me.
Another rifle that shoots small groups is a custom No. 5 SMLE that I’ve converted to .219 Donaldson Wasp. The scope on this one is another one that’s vintage and all-steel — a Redfield 2-7x variable with what appears to be a 28mm or 30mm objective. The crosshairs are even finer than those of the vintage Weaver, and the dot at the intersection is also smaller. This rifle should be good for prairie dogs out to 300 yards, as well, but I feel the power of the scope limits the range to 250 yards for targets so small. Coyotes to 300 yards are possible because they’re much larger. So, I’m saying that a 7x scope works well at 250 to 300 yards, but the maximum effective distance depends on the target — at least for me.
It might be an ugly rifle, but this .219 Donaldson Wasp can shoot. It has a custom Shaw barrel of my own design with a faster twist. And the little Redfield scope is plenty good for what I want to do.
Going the other way, I absolutely love Leapers’ line of long eye relief scopes that produce 1.5-4x. These scopes may not make the target appear large, but they can’t be beat for clarity. For value, I don’t think the Leapers 1.25-4×24 long eye relief scope with the one-inch tube has any equal. It’s currently priced at only $85, which is very little for such a great sight. It would be ideal on big bore airguns of all kinds, as well as powerful springers that won’t be shot past 50 yards — rifles like the Beeman R1 in .22 caliber, for example. Yes, the parallax is set at 100 yards, but I have found that when the magnification is this low, it doesn’t matter where the parallax is set. This scope would be ideal on a New England Firearms (NEF) single-shot rifle in .45 Colt or .44 Magnum or on any small carbine in a pistol caliber.
What about more powerful scopes?
There are a FEW applications for the scopes with power up to 32x and more. Field target competition is one such game — not because of the additional aiming precision, but because that extra power helps you resolve small objects out at 55 yards, so you can determine ranges with the parallax adjustment more precisely. When you can focus on very small objects at long distances, the scope helps to determine the range to them. And long-range target shooting is another time when a higher-powered scope is needed. When you’re going for the absolute best group that can be fired from a gun, the scope must be powerful enough to reduce the aiming error to the smallest fraction of an inch.
Talk all you want about big scopes. Try carrying around one like this for a couple hours! A Daystate Harrier is dwarfed by this monster Tasco Custom Shop 8-40×56.
HOWEVER — and this is the whole point of this discussion — it doesn’t take the Hubble Space Telescope to shoot good groups at 50 yards. As you clearly saw in my report on the Conquest, I did it with only 4x. Consider that when thinking of your next scope. You can have a handy package that carries easily and handles rapidly or you can mount the biggest bragging-rights scope money can buy on your air rifle and then suffer for it.
Clarity
Clarity goes hand-in-hand with accuracy when using a scope. In fact, I think clarity is the single most important attribute a scope sight can have. There are technical means of determining relative clarity in scopes. The most common one is determining how many line pairs the scope can resolve in a standard test. Clarity is actually a statement of the scope’s ability to resolve an image. When we say clarity, we mean resolution.
I am not an optical engineer, nor am I qualified to discuss how scopes are tested. And the subject is so technical that even if I could discuss it, not everyone would understand what I was saying. I’m going to reduce the resolution/clarity question to something we can all understand.
I have a simple test I use to subjectively determine the relative clarity of a scope. All I do is point the scope at the roof of my neighbor’s house about 25 yards distant and look at the shingles. If the shingles appear sharp, with the vertical joints well-defined and the abrasive particles standing out clearly, I know the scope is clear. If any of the image is muddy, even after the scope is adjusted for that range, I know the scope is not as clear as I would like it to be.
I developed this test a couple years back when I pitted a Hawke scope against a Leapers scope of the same power and specifications. Until that test I thought nothing affordable could ever beat a Leapers scope; but in that test, the Hawke scope emerged as the clearer sight. It was also more expensive, but it didn’t cost twice what the Leapers did, as I remember. The shingle test is a good one for any scope you intend using for target shooting or hunting, as nothing in the field will exceed the fineness of the image the shingles can give.
If you don’t have access to shingles, anything with a fine grain will work just as well. Old wooden fences are another way of testing the resolution of your scope. Just be sure to always test every scope at the same distance and using the same object, and your test will soon become very refined.
When you buy a scope, you usually can’t perform the test I just described. You have to take someone’s word on the clarity. But I have a couple tips about that.
1. Multi-coated optics on inexpensive scopes are usually not as clear as single-coated lenses. Leapers has used a single coating of emerald for as long as I’ve known them, which is why they’re as clear as they are at such a low price. You might give up something else with single-coated optics, such as five minutes hunting time in the morning and evening, but that depends on what kind of coating it is.
This deserves an explanation. While multi-coatings can be applied to make optics perform their best, the hype of multi-coating is too powerful to be overlooked by the marketing departments of many manufacturers. Therefore, the cheap scopes are multi-coated without regard to light transmission or any other enhancements. As a result, these multi-coated optics are much like airguns that shoot over 1,000 fps — lots of hype but you’re giving up accuracy. On the other hand, expensive multi-coated optics deliver superior performance.
2. The objective size doesn’t matter as much as you think. You don’t always need the 56mm objective to see clearly. The quality of the lens material and the optical coating(s) matter more than the objective size.
3. A 30mm scope tube will be noticeably clearer than a one-inch tube, if all else is equal.
4. You can live with a lower-power scope if it’s also clear, but a high-power scope that doesn’t focus or is unclear is the worst headache imaginable.
The bottom line
Considering just these two subjects — power and clarity — shop for a lower-power scope with a 30mm scope tube and a single lens coating. From what I saw in the Leapers booth at this year’s SHOT Show, there will soon be a flood of very clear scopes at good prices (but not cheap!) hitting the market this year.
Price
Stop shopping for scopes by price, alone, and then condemning your rifles, pellets and the entire hobby of airgunning when things don’t work out! Most cheap scopes are cheap for a good reason. I understand trying to buy the best scope you can afford, but stop focusing on the price so much.
Cheap scopes aren’t usually that much worse than more expensive scopes. I say “usually” because I’ve seen a couple brands that can be counted on to be bad. But cheap scopes don’t pass through the quality controls that most of the more expensive scopes do. You’re far more likely to end up with a lemon if you buy the rock-bottom scope.
And this final tip is worth the price of this entire blog: Most combos (rifle and scope for one price) that are put together by manufacturers are put together by their marketing departments to get rid of the cheap scopes nobody will buy! However, when a combo is put together by a dealer, that usually isn’t the case. Pyramyd Air has put some very decent scopes on some of their combos because they realize their customers really care which scope comes with the gun. The more the combo costs, the better the scope will probably be.
But watch out for those manufacturer combos!
