Air Arms Pro-Sport: Part 4
by Tom Gaylord
Writing as B.B. Pelletier
This report covers:
- Pro-Sport trigger
- Based on the Rekord
- Set trigger
- Rekord is not set
- What is dangerous?
- Hair trigger
- Fingers with neuropathy
- Cold fingers
- So what?
- TX trigger
- Mach II trigger
- Pro-Sport trigger adjustment
- Stage one
- Stage two
- But wait…
Today I show you the trigger of the Air Arms Pro-Sport rifle that I’m testing. I said in Part 2 that I was going to show how to adjust it in Part 3, and then I breezed right past that and shot groups instead. The reason I did is because this trigger was adjusted perfectly as the rifle came to me from the factory. Stage two breaks at 14.8 ounces. It’s far too light for sporting use but perfect for shooting from a bench in a warm environment.
I normally don’t take the time to write about adjusting triggers for you, though in the recent past there have been several exceptions. The Pro-Sport trigger, which is identical to the TX200 Mark III trigger, needs to be another exception, because it is one of the finest sporting air rifle triggers on the market.
Based on the Rekord
To understand the Pro-Sport trigger we first need to understand the Rekord trigger that preceded it by several decades. The Rekord is a multi-lever trigger that is very closely related to a set trigger that can release in fractions of an ounce. But a Rekord is not a set trigger.
This is the Rekord trigger. Yes, I photographed it from my Beeman R1 book, because I apparently no longer have the original artwork.
Here is a look inside the sheetmetal trigger box that holds the Rekord trigger parts. Also taken from my R1 book.
A set trigger is “set” (armed would be another good word) by moving its parts into position so that the slightest pressure will make it operate. It can be a single trigger blade that is pushed into the set position, in which case it is called a single-set trigger. Or, there can be a second trigger whose only job is to pull all the trigger parts into position — “setting” or arming the real trigger. When there are two trigger blades it is called a double-set trigger.
Rekord is not set
But the Rekord trigger is never set. It is a proper two-stage sporting trigger. It should always have a first stage that is light and stops when resistance is encountered! That resistance is the effort needed to pull the second stage to the release point, firing the airgun. That second-stage resistance can be adjusted very light — so light, in fact, that it becomes dangerous.
What is dangerous?
If a gun fires because the shooter has his finger in the triggerguard and it touches the trigger blade unintentionally — that is not an accident. That is a stupident! I have done it. Maybe you have done it, and I know stories that I’m sworn not to reveal about people nearly everyone knows who have done it. That is not an accident and it is not the trigger’s fault.
What IS the trigger’s fault is when the gun fires because the weight of the trigger blade alone causes it to move and the sear to release. Think it’s impossible? Think again. There are set triggers that can be set that light and they fire when the muzzle of the gun is elevated and the trigger pivots back on its pin because of gravity. I have seen guns with triggers set that light. Those are called hair triggers because supposedly the force of one human hair against them will set them off. But many people call a one-pound trigger a hair trigger because, to them, it’s so light that it fires before they are ready.
Then there are triggers that fire all by themselves because their sear angles are not correct. All it takes to fire these triggers is to reduce the friction and give the trigger a small push. A 100-pound coiled mainspring pushing against a piston (when a spring-piston rifle is cocked) can provide such a push. These triggers may function perfectly for many years and then fail when they are lubricated with a high-tech lubricant like moly that drops their friction below the point needed to hold them. I have a hole in the ceiling of my office from a BSF S55N that fired unexpectedly from this problem. A slipping trigger is a well-known fault of BSF triggers.
Fingers with neuropathy
Maybe you have neuropathy in your fingers and don’t recognize it. It comes in many forms — one of which is you loose sensitivity in your hands, including your trigger finger. You know that it’s getting harder to pick up postage stamps and coins, but it hasn’t dawned on you that a trigger can also be a problem. You can’t feel the blade until you put 5 pounds of force on it, by which time the gun has already fired.
When you are out hunting in cold weather your fingers loose their sensitivity, and a one-pound trigger becomes a hair trigger. Cold weather calls for 5-pound triggers, which is the military standard for nearly every nation on the planet.
The Rekord trigger was designed to be a nearly foolproof two-stage trigger that can be adjusted to suit your preferences, within reason. And, it’s the “within reason” that catches many airgunners. For instance, I just read on one forum where Rekord trigger adjustment screw 52B — the one Beeman has recommended for decades that you never adjust — is laughed at! This forum calls that adjustment a fake. Well, that adjustment determines how much sear engagement stage TWO will have in the trigger. If someone comes along not knowing the consequences and wants an 8-ounce single-stage trigger and they adjust screw 52B to get it, they have just adjusted out all the “proof” in “foolproof,” and what does that leave?
But this report is about the trigger in a Pro-Sport. Well — until you understand how a Rekord trigger works you will have a hard time understanding the more sensitive trigger found in the Pro-Sport.
Mach II trigger
Many rears ago I owned a Mach II trigger (a Rekord trigger replacement) that was custom made by Ivan Hancock. It looked deceptively simple, yet it could be adjusted to a razor’s edge. I no longer have that trigger but let me show you what it looked like — again from my R1 book. Before you get all goose-pimply, please know that the Mach II trigger sold for around $250 in the mid 1990s. It would be a $400+ trigger today.
The Mach II trigger exposed. It looks almost identical to the Air Arms trigger graphic above. Two screws in the trigger blade (their holes can barely be seen in this photo) put pressure on the part that Air Arms calls the bottom sear when the trigger is pulled. Notice how close these screws are in this blade.
I showed you the inside of the Mach II trigger because it is nearly identical to the Air Arms trigger except it’s “box” is made of brass and has a brass plate that can be removed to look inside. The Air Arms trigger is inside a sheetmetal box that also opens like this, but I used the Mach II trigger photo that I already had. After shooting the Pro-Sport for record I just don’t want to spoil that gorgeous trigger pull that it came with!
Pro-Sport trigger adjustment
For this discussion we will concentrate on those two adjustment screws that pass through the trigger blade. I hope you understand how a lever works, because these two screws rely heavily on that principal.
The Record trigger doesn’t have these screws. It depends on the shape of the trigger blade (two raised humps) to accomplish the same thing as these two screws, but its shape cannot be adjusted. So people adjust that trigger all that they can, which turns out to be screw 52B. The Air Arms trigger is therefore much more adjustable, and to a finer degree.
Stage one is adjusted by the front screw which is also the shortest one. It presses on the bottom sear (the lever) at a point farthest from the fulcrum. That means it moves farther and applies more energy to the lever, but all it is pushing against is the trigger weight spring, so the effort is miniscule. The further in that screw is adjusted the shorter stage one becomes. The trigger blade stops when it encounters more effort. Now, where would that be?
The trigger stops when the stage two screw touches the bottom sear. It is closer to the fulcrum and therefore applies less force because its mechanical advantage is less than the stage one adjustment screw. But the stage one screw is still pushing against the bottom sear, too, so the effort to move the trigger blade increases by an amount that can be felt. This point is felt as the stage two stop just before the gun fires.
If you understand what I have explained so far you can see why the Air Arms trigger is capable of so much finer adjustment than a Rekord. Both stage one and stage two screws act in unison to control how this trigger responds.
Yes, there is more but it’s only found on the Mach II trigger. It’s the other screw that passes through the trigger floorplate next to the pull weight spring. That is a positive trigger stop. If you look at the Air Arms trigger you see there isn’t much room to put in a stop screw like that. So they didn’t. This is the one area in which the two triggers differ.
What I have shown you today are the fine adjustments that make the Air Arms Pro-Sport and TX200 Mark III triggers the finest adjustable triggers in the sporting spring gun world today. I have told you where the trigger on my rifle is set, but I have avoided messing with it because it is so right on as it is.
So what comes next? I have received a 12 foot-pound tuneup kit from Vortek, and I plan to install it next, then test the gun for velocity and accuracy again. And I hope to mount the Meopta scope for that test. After that, who knows?