by Tom Gaylord, a.k.a. B.B. Pelletier
Maheen Na is this week’s Big Shot of the Week on Pyramyd Air’s facebook page.
Blog reader J-F suggested this blog, and other readers chimed in with their approval. Since this is a topic that I’ve been quietly studying for more than a decade, I welcomed the opportunity to talk about it today.
The thing that got me started wondering about this topic was a tuneup kit for the Beeman R1/HW 80 made by Ivan Hancock. Called the Mag 80 Laza kit, it took my R1 to almost 23 foot-pounds of muzzle energy, yet when it fired it felt like a 10 foot-pound gun. There was no recoil, no vibration — no sensation of power. It’s what I call a balanced tune because it masked the power in the ultra-smooth behavior. That rifle also had Hancock’s Venom Mach II trigger, which is highly refined and based on the Rekord, so the trigger was perfect, as well.
The Mag 80 Laza kit tune required 50 lbs. of cocking effort, plus the rifle is very large and heavy. From those perspectives, it was not ideal. But in all other respects, it was a dream to shoot. That started me wondering what makes a great spring-piston air rifle.
I’ve noticed that power does affect the performance of a spring gun, but it isn’t a linear relationship. There are plenty of weak Chinese springers that will testify to that fact! What I’ve noticed is that the likelihood of good performance diminishes rapidly as power increases. To put it simply, it’s much easier to make a 6 foot-pound spring gun that performs well than it is to make one that produces 20 foot-pounds. But that’s NOT a guarantee that 6 foot-pound guns are all good or that 20 foot-pound guns are all bad. My Whiscombe generates very close to 30 foot-pounds in .25 caliber and is still very smooth.
Vibration is one killer of great performance. I have an HW 55SF, a target rifle made without the barrel lock common to most HW 55s. It’s really just an HW 50 with HW 55 markings, but it’s a recognized model. And as soft as it shoots, it buzzes. That is very disturbing — to have a super-accurate, easy-cocking target rifle that feels like a bottle of mad wasps when it fires.
And, yet, the aforementioned Beeman R1 with the Mag 80 Laza kit and triple the power was super-smooth. Go figure!
The point I’m trying to make is that vibration ruins a shooter’s impression of the gun — no matter how accurate it may be. And, as the power increases, so does the likelihood of vibration because the parts are all under greater stress. While low power is not a guarantee of good performance, a lot of power does make smoothness that much harder to achieve.
But power has another bad aspect: Recoil! I have an HW 55 CM that does not vibrate, but it has a jarring thump when it fires. Maybe that IS a kind of vibration, but it’s felt in the face as a slap delivered through the cheekpiece of the stock. My Beeman R1 with the Mag 80 Laza kit did not recoil as much as this puny little HW 55. Once again — go figure!
Mac has entrusted me to tune his HW 55 Tyrolean that he says is near coil-bound. I can do that by simply shortening the mainspring, but guess what? The cupped cheekpiece on the Tyrolean stock will knock his teeth out! He doesn’t know that because he owns several other Tyrolean spring rifles that all shoot very nice, but what he hasn’t considered is that all of them have the sledge anti-recoil system installed in the stock. That isolates the shooter from the recoil that would slap him in the face with every shot.
Lastly, I have a Beeman R8 that’s been tuned to just more than the power of an HW 55. That rifle has a Tyrolean stock, as well, but all the right things were done to eliminate vibration and recoil, and it’s a sheer dream to shoot.
My Beeman R8 has a Tyrolean stock, but the powerplant is tuned so well that you don’t notice any vibration or recoil.
When we consider power in a spring rifle, we need to understand what it does to the shooting behavior. Yes, there are powerful spring rifles that do shoot smoothly, but they didn’t happen as a happy accident during manufacture! They had to be engineered very carefully from the start to eliminate excess vibration and recoil.
I could have lumped cocking effort with power because it does relate, but I wanted to address it separately — as a way of comparing how the right cocking effort contributes to your enjoyment of a spring gun. I guess the poster child for good cocking effort has to be the Diana 27. It cocks so easily that you want to shoot the rifle all day long. Then, when you do shoot it — if it’s has been tuned properly, which is nothing more than a good lubrication for a model 27 — it neither vibrates nor recoils. That will put a smile on your face every time! Add in a properly adjusted trigger, and the Diana model 27 may well be the most pleasant spring rifle in the world. But others are nice, too.
The FWB 124 cocks very easily for the power. Its firing behavior is both buzzy and has some recoil, but that can be tuned out. A properly tuned and adjusted FWB 124 is a dream to shoot.
The Air Venturi Bronco is another winner. I selected the action after shooting the original Bronco (RM-10 made by Mendoza), which was a youth-sized rifle with a horrible Euro-modern stock. The cocking effort was/is light, the trigger is light and positive, and the vibration is at a minimum. There’s a little recoil, but I’m guessing there doesn’t need to be. The Bronco is very close to an ideal spring rifle.
Blog reader Duskwight is building a dual-opposed piston spring rifle that’s based on the Whiscombe rifle, in concept. The design is entirely his own, but he wondered if gas springs might make a significant difference. I can tell him they will because gas springs do eliminate a lot of the spurious vibration that goes with the spring-piston powerplant. As smooth as my Whiscombe is, it still vibrates a little when fired. I’m betting the “Duskcombe” is going to be entirely neutral when it fires.
So, a gas spring is good for canceling vibration. Does that mean it’s also the best solution for a spring-piston rifle? Yes and no because a gas spring changes the cocking effort no matter how hard or easy it is to cock. A metal spring increases in effort as the spring compresses. It’s easy in the beginning when the mechanical advantage is low and harder toward the end when the mechanical advantage is high. But a gas spring has the same resistance throughout the entire cocking stroke. Even a light gas spring starts out hard at first. Therefore, I don’t think that a gas spring should be used on the ideal air rifle…unless a superior cocking linkage can be found to correct the gas spring’s problem.
Size and weight
I have a Walther LGV Olympia target rifle that’s a breakbarrel springer. The cocking effort is about 15 pounds, which makes it a winner. And the rifle neither vibrates nor does it recoil. It’s a target rifle, so you know it’s accurate. Even the trigger is about perfect. It’s the perfect spring gun, right? Wrong! The Walther LGV Olympia is very large. At 10.5 lbs., it’s also quite heavy. You wouldn’t want to lug it around all day no matter how much fun it is to shoot. Size does matter; and in this case, smaller and lighter wins the day for a general purpose airgun.
The Walther LGV Olympia target rifle has just about everything you want in a spring gun, but the package is too large and heavy for general use.
Once more, the Diana 27 comes to the forefront. It’s not just light at just over 6 lbs., it’s also sized right. The forearm and pistol grip are both slim enough to almost be called dainty…but not quite. The BSF 55 was small and light and had a great trigger. But it was somewhat hard to cock, where the FWB 124 with the same power was much easier to cock. But it was also heavier, so there was a tradeoff.
When all is said and done, the Diana 27 may be the best air rifle ever made.
Remember the topic
Everything in this report is resolved by the right PCP. But the title says we’re talking about spring guns, so that doesn’t count.
How hard is it to make a great springer?
To be great, in my opinion, the gun must:
— be light
— have a slender and well-shaped stock
— be easy to cock
— not have any vibration
— be relatively free from recoil
— have a great trigger
— be accurate
Getting all of that in one package is a daunting challenge. And it isn’t as straightforward as you think it should be, either. You take a “perfect” gun to a well-run airgun factory and ask them to produce it, and they’ll get it wrong every time. They will first take your perfect gun apart and analyze it. Then, they’ll try to match what they see, component by component, to their manufacturing processes. I’ll give you a couple examples.
Your gun has a trigger with contact surfaces that are polished to a mirror finish and hardened to Rockwell 66C. Company A is examining the rifle and uses a CNC mill to make their trigger parts, and they can get a good finish but not one as good as what’s on the trigger you have given them. To do that would require a $35,000 investment in new machinery and tooling. But worse than that, they would have to slow down production to get your level of finish, so each trigger they make would cost about $29 instead of the $17 it cost in the rifle you gave them.
Company B is another reputable airgun maker who looks at your rifle. They don’t like to finish steel parts by hand, preferring instead to tumble them in a graduated set of vibratory tumblers that progressively put a satin luster on the metal before bluing. They don’t employ any hand polishers, nor do they have the machinery needed for polishing the parts. They tell you what they can do, but it falls short of your expectations.
And so it goes. Company after company can make most of what you want, but not everything. This is one reason people cash in their retirement plans and start their own companies to “do it right!” Sometimes, it works and a Weatherby is born. But usually it results in a failed attempt to make something so simple that they wondered why nobody was doing it before they came along. Then they got educated — at a great cost.
I think I know how to make a single good air rifle. Making them in volume is the real trick!