The GRT III Trigger

By Jerrold Paul Shelton

Upland Hunter.Net E-Magazine

If you've got a sharp eye for detail, and at least a passing familiarity with Gamo rifles, you'll note something just a wee bit different about the trigger blade of the Gamo Shadow in the photo.

The GRT III trigger dramatically transforms Gamo rifles

Here in California, most of the animals classified as "resident small game" in Section 257 of Title 14 of the Code of Regulations can be legally taken with air rifles, and this includes resident upland game birds, such as mountain quail and chukar partridge. Because of the habitat these birds favor, a light rifle can be a definite asset for those electing to use an air rifle to pursue them, and at 6.25 pounds, sans scope and mounts, the Gamo Shadow has a power to weight ratio that is virtually unmatched compared to other spring-piston air rifles.

The GRT-III trigger transforms the Gamo Shadowfrom a respectable rifle to one of the best air rifles available at any price for most California upland game bird shooting.

In the opinion of many airgun enthusiasts, the "GTX" drop in trigger formally marketed by Charlie's Springer Works was one of the best products to hit the adult air rifle market in the last decade.

Why? Because of what this relatively inexpensive little item does to take a nice rifle to a whole new level of performance and shootability.

But as good as the GTX trigger was, Bob Werner, known to many in the airgun community as "Charlie Da Tuna" and the man behind Charile's Springer Works, found room to make his "drop-in" trigger even better. Rather than just leave well enough alone, as many would be inclined to do, Mr. Werner incorporated some improvements in the latest incarnation of his excellent trigger, now known as the GRT III. The differences are subtle, and have more to do with insuring that the trigger will be easy for end-user installation and provide the intended improvement in trigger feel, regardless of manufacturing tolerances present in the rifles it is intended to work with. In other words, if you are already one of the hundreds of satisfied customers who purchased a GTX trigger, you'll be equally satisfied with the new "GRT III" version.

Compared to the former version, the newer GRT-III trigger blade has beveled edges that make it more comfortable and more ergonomic to use, as well as a serrated face to prevent finger slippage, rather than the smooth surface of the former product.

Our trigger arrived in a well-padded shipping envelope, and came with a hex key for adjustment, as well as very detailed instructions that proved extremely easy to follow.

While Mr. Werner provides the hex key for fine tuning, each of his drop-in triggers is fully adjusted and tested prior to shipment, so no tuning should be necessary. You simply follow the instructions for removing the old trigger parts that his blade replaces, and in most cases, the trigger feel you get will be fine, as is. Installation is very easy, and took me a little under 10 minutes when putting the trigger into a Shadow 1000.

The new trigger went into a rifle that is a couple of years old and has had at least 7,000 shots fired through it. Before swapping the factory trigger parts with Mr. Werner's new blade, I used my RCBS trigger pull gauge to measure the pull weight. In stock form, the trigger on the rifle used for the swap broke at 4.25 pounds, as Gamo advertises it to do.

Part of the bad vibe that the standard Gamo trigger gives off is due to a rather mushy feel between the "first stage" of the pull and the "second stage." This is due to the fact that the Gamo trigger isn't really a "two-stage" trigger at all, but a single stage unit made to feel like one with a fairly stout trigger return spring that goes unused when Mr. Werner's trigger blade is installed.

The geometry of Mr. Werner's trigger bladeis such that it converts the function of what was really a single-stage trigger into a true two-stage unit in which each stage does useful work. As a result, sear engagement remains sufficient for safety, while overall feel is improved dramatically. In use, you "pull through" the first stage to the "bump" where the second begins and just that little bit of added pressure in the second stage results in discharge.

The resulting pull after installation of Mr. Werner's trigger blade measured 1.18 lbs on the RCBS gauge. This is significantly lighter than the factory specification and, in fact, is nearly a full pound lighter than the pull weight of the triggers on my R-Series Beeman rifles, which I set to break at 2 pounds. The light pull that results from this modification may take some shooters a bit of getting used to, but once you do, you'll wonder how you managed to shoot your Gamo rifle accurately with its factory trigger parts in place.

The problem with the Gamo trigger as I see it isn't solely the pull weight, which, while high by traditional adult air rifle standards, is pretty close to the weight of an old Springfield or Garand, or a host of old-school sporting rifles that firearms shooters are familiar with. I can work with that, but whereas the moment when the trigger breaks and the sear trips on a two-stage military trigger like that of a Springfield or Garand is largely the same from one shot to the next and is thus predictable, the trigger pull of the Shadow receiving the new trigger blade wasn't when all of its factory trigger parts were in place.

The new trigger blade from Mr. Werner, however, results in a predictable let-off, which feels the same with every pull.

One thing that this trigger doesn't address is the lack of a "resetable" sear in the Gamo mechanism. A partial pull of the trigger will alter the sear engagement and lessen it. The Gamo trigger is like that even with the factory trigger parts in place, by the way. If you start to pull the trigger and then decide not to complete a shot, you still need to re-cock the rifle to fully re-set the sears for maximum engagement, just as you should have been doing with the rifle in an unaltered state. There is also some over travel present after the sear trips with the new tigger blade installed, but it isn't enough to get excited about.

The excellent "Rekord" trigger unit used in R-Series Beeman rifles is the standard by which spring-piston air rifle triggers are measured. How, then, does this modified Gamo trigger with one of Mr. Werner's drop-in trigger blades stack up?

Pretty well. How close it comes depends on the individual rifles in question and also on the sophistication of the shooter doing the comparing, and their ability to discern subtle differences in feel. With the GRT trigger blade in place, the difference in trigger feel between a Gamo rifle and an R-Series Beeman really is one of subtle degree, rather than radical dissimilarity. Some shooters will notice the difference.We're not sure that most would.

This trigger doesn't make a rifle more accurate. What it does do is make the rifle easier to shoot accurately.

Here, then, is a product that should definitely appeal to shooters who find much to like in Gamo's Shadow and Hunter lines of spring-piston air rifles, but find the factory trigger set up to be most charitably described as "deplorable."

Other air rifles may indeed be more joyous to behold than the Gamo line.

Fortunately for hunters not so aesthetically bent, squirrels, rabbits, mountain quail, and Chukarcould care less about such things.

Go to www.charliedatuna.com for information on how to order one these excellent trigger blades, which fit the Shadow, 220, 440, CFX, and other Gamo rifles, as well as the Remington Summit andcertain Chinese and Theoben rifles using the Gamo-type trigger mechanism.

By Jerrold Paul Shelton

Upland Hunter.Net