This report covers:

  • Something else
  • AirForce
  • 21-speed bicycle
  • TalonSS
  • More power?
  • Other power adjustments
  • Setup
  • Another way to get power adjustability
  • One more way to change velocity
  • The thing is…
  • Summary

I was all set to do the velocity test on the Gauntlet 2 PCP rifle today when it suddenly occurred to me that I was stressing out about how to test that rifle. Some of the reason for that stress will come out in today’s report, because I want to talk to you about the downside of adjustable power.

The Gauntlet 2 doesn’t have adjustable power, but it does have a lot of shots and it fills to very high pressure, and I have been asked to test odd things, like how many shots the test rifle gets with a fill to 3,000 psi. That got me thinking about how involved and difficult it is when I test a gun with adjustable power. And that is where today’s report came from.

Something else

Many people seem to want what they don’t have — or at least they think they do. If they hear about something they wonder aloud why it wasn’t also designed to do something else. Let me give you some illustrations.

AirForce

When I worked at AirForce Airguns I took all the calls that came in about modifying the rifles. One guy wanted to shoot as fast as possible, so he tethered his Condor to a helium tank and claimed a muzzle velocity of 1,700 f.p.s. Another guy was fanatical over having his air tanks “balanced” to give the same velocities at the same power settings. He sent me his rifle and spare tank, asking me to “balance” the valves in both tanks to do just that. The thing is — that is almost impossible to do. He was of the opinion that if we made the rifle surely we could set up each tank to shoot at the same velocity on the same power setting. But it can’t be done by any means beyond sheer luck, any more than two V8 car engines of the same model can be tuned to give exactly the same power on a dynamometer at all speeds. Sure, you can get two engines to read the same at a certain RPM, but change that RPM and they will not be the same.

Another organization wanted to shoot our TalonSS rifles at 500 f.p.s. and no faster than 600 f.p.s. Now that is more feasible because they gave us a range of velocities. And the TalonSS will shoot that slow right out of the box. You just won’t get a large number of consistent shots from it at that speed. You might start out at 508 f.p.s. and by shot 20 you’re up to 736 f.p.s. Why? Because the valve in the rifle was really designed to shoot .22-caliber pellets in the 850-950 f.p.s. range. Yes, it can be adjusted slower, but it doesn’t like to remain there. People may want that kind of flexibility, but getting it is a whole other thing.

That organization was the National Rifle Association and the reason they wanted our rifle to shoot so slowly was because they were using Daisy pellet traps on their public range at their annual meetings where our rifles were being used. An 800 f.p.s. rifle would soon shoot through the thin steel backer plate of the Daisy traps. They also wanted to get lots of shots on a fill because the public was lined up deep to shoot our airguns.

The solution was to use an air valve we called the “double restricted” valve in house. It had a lighter return spring and a very tiny air orafice in the valve stem. John McCaslin built it just to see how many slow shots a Talon SS could give. After hearing the NRA’s requirement for the range, he built several more such valves and they have been on the guns we use at the NRA public range ever since. You can also buy one of those valves in a new tank today. It’s called a MicroMeter tank.

Yes, such things can be done when there is a solid reason to do so and also a solid specification to meet. And yes, the same TalonSS rifle that can shoot that slow can also be brought back to full power with a standard air tank and valve — that is the beauty and wonder of the AirForce system. But you need to understand that the power adjuster wheel on the left side of the rifle is not enough by itself to do both things — low speed and high speed with consistency.

The guy with the helium tank was a crazy science experiment. Imagine going into the woods searching for squirrels with an air rifle tethered to a 5-foot steel tank of helium! The guy who wanted balanced tanks was just too lazy to check both of his tanks over a chronograph to find where the power adjuster on the rifle had to be set for each tank to give him the same velocity.

21-speed bicycle

I have a 21-speed bicycle and it does use all 21 speeds to accomplish different things. You can pedal easily up a steep hill in the low range and first gear. And you can fly like the wind on a level road or a slight downgrade in the high range and gear seven. But that bicycle was built around those 21 speeds. That is one of its principal performance features. Guns aren’t made to do that. They are made to hit things when they shoot.

TalonSS

You can get a .22-caliber TalonSS to shoot consistently at 775 f.p.s. up to about 850-875. In that range the rifle can be very consistent for a decent string of shots. Heaven forbid that accuracy should enter the equation, but if it does I have found my TalonSS to be most accurate with .22 pellets weighing 14.3 grains exiting the muzzle at around 820-830 f.p.s Do you see how specific things get when you actually want to do something? So my adjustable TalonSS power wheel is set at about 8.10, or so. I say “or so” because my SS was not engraved with the power settings. So I have to guess where the adjuster is set.

Find a Hawke Scope

More power?

If you want more power from a TalonSS the easiest way I know of to get it is to add more barrel. And AirForce guns are made to swap different lengths of barrels in different calibers in minutes. By installing a 24-inch .22 caliber barrel on a TalonSS after removing the 12-inch barrel, the power jumps from about 22-23 foot pounds to 43-44 foot pounds with no other changes. However, you loose the quieting that the shorter barrel has because the longer barrel sticks outside the frame. The rifle also becomes longer overall.

Does the longer barrel still have adjustable power? Yes it does. In fact, because the barrel is longer the adjustment range becomes a little larger. The rifle can dip down to almost the high end of the shorter barrel, but of course with a lot less air being used. So more shots on less air. But the difference isn’t that great. You don’t double the number of good shots. You might get 5-10 more.

power adjustment
The power adjustment wheel on a TalonSS is designed to refine your power within a narrow band of velocities.

Other power adjustments

Let’s look at another power adjustment — the one that comes on the Beeman P1 pistol. There is a low power setting where the piston is caught by the sear at one place in the cocking stroke and a high power setting where the piston is caught with the mainspring more fully compressed and the piston stroke much longer. Even though the pistol has those two settings I seldom use the lower setting. The trigger breaks more cleanly on the high power setting, so that’s where I cock the gun every time.

The Crosman Mark I and II Target pistols have the same arrangement, only it’s the hammer that gets caught in either of two places. But the trigger is crisper on the high power setting, so that’s where I cock the gun every time.

Setup

I know that people who are dreaming about getting an airgun with adjustable power spend time daydreaming about all the things they can do with it. People who own airguns with adjustable power spend their time setting it up to do its best at just one power setting. That’s the difference between dreaming and doing.

Another way to get power adjustability

With the .458-caliber AirForce Texan you can change the weight of the projectile to change the power dramatically. For example, if you shoot a round ball that weighs 143 grains, it goes out the spout at 966 f.p.s. and gives about 296 foot-pounds of energy, but if you shoot a 405-grain bullet it exits at 750 f.p.s., giving about 506 foot-pounds at the muzzle. That’s more than a 200 foot-pound energy difference from a 216 f.p.s. velocity difference. And all you did was change what you shot!

One more way to change velocity

Ever hear of a multi-pump pneumatic? They are sold on the basis of user-adjustable power. But users quickly learn that the number of pump strokes also changes where the pellet lands. It’s not a simple 3 pumps for 15 yards and 8 pumps for 40. Things other than the trajectory change as the number of pumps change.

The thing is…

The thing is — you don’t make these changes without changing where the projectile impacts. And you also change the size of the group, which means changing the accuracy of the gun. Since the main objective is to hit what you shoot at, when all the silliness is stripped away the bottom line is you set up the gun to shoot one way accurately and then you do it. You don’t keep changing the velocity or the power of the gun.

Summary

Adjustable power sounds great, and it really can be, but the user has to understand all that is involved.