I had an e-mail this morning with a post attached from the Gamo page on the yellow forum regarding the Fat Pin bushing that Ken Fawcett “just thought it upâ€. Right!!! Well maybe he just thought it up but his “just thought it up†concept and info has been around for years and articles regarding it has been published many times and many have read about it. There is also an article complete with drawings somewhere too. I used to have it but can't find it. In fact, at one time Russ Best published something about the bushing thing and it was published in the Fun Supply back pages somewhere years ago. I’m sure it’s probably still there someplace. I also published an article called “B-19 trigger fix†complete with graphic illustrations on my website on the "Airgun Info" page when I first put it up but pulled it off a few months later.
The first time I became aware of it was from James Kitching four or five years ago, maybe even longer than that. At that time, he and I as well as other like RB played around with it as well as a fella named Collins in Hawaii and another guy named Ken from KC. In fact Collins sent KC Ken the information about it (I still have the e-mail) and then Collins, Ken and I all shared quite a number of ideas and results over the span of a few months. James said we were wasting our time and that we would never be able to attain our goal with the bushing and spring approach, and that the only way it would ever happen is to redesign the trigger itself and the lever, and he was right then and right even to this day.
I have about 30 or 40 B-18’s and B-19’s as well as a few Gamo's out there (Gamo's were not very popular back then) that I did trigger tunes on years ago and incorporated variations of the mod into it using several different approaches but eventually canned it all together. Although it did shorten and lighten the pull, it was even more difficult determining when it would break. In fact, some of the guys went so far as to make it stock again because at least it would shot the exact same way time after time and is something that most shooters wouldn't identify with or recognize even when they are looking for it. That often impacts consistency and accuracy.
All that bushing does is it takes out some of the slack that is hidden by the strong trigger return spring. Without a return spring, you do reduce the pull weight pull of the trigger spring but you have little sense as to when the sear is being engaged as well as the trigger free play is no longer contained. If you insist on using the bushing approach, you would be much the wiser leaving the spring in and bending it to adjust it to a bit lighter pull. With the spring removed, it can also possible make the gun dangerous without you knowing it, especially as the sear begins to wear as I found out on my old B-19. Because the Gamo uses far better steel in the sear and lever than the Chinese gun I would expect that to be less of a problem. I did eventually make a few different return springs and got one that I found to be acceptable but it still didn't resolve the basic problems with the Gamo/Theo ben type trigger of not having a fully functional operating positive two stage trigger..
Anyhow, I didn't really like the way that it was working, or maybe I should say wasn’t working, and when James suggested that I discontinued doing the mod, I discontinued doing it. As James put it, it was, in James’s words, “a Cajun Fix†and it wasn’t addressing the real issues anyhow and of course he was right.
But...with all of that being said, if you do want to play with the concept, a few things of interest. The original spring return spring wire diameter in the Gamo is .040 or about 1.03 mm. Make one out of .025 or .63 mm diameter wire. That will be a big help in the spring pull weight and the overall trigger pull weight. The initial thought was that the bushing would need to be made from a hard material but brass, a good grade of Aluminum or any steel will do but does need a smooth finish on it for the contact with the lever. The intermediate lever does not have an excessive amount of pressure applied to it like the sear does, especially like a direct release sear. As James said though, it is a band-aide "Cajun" fix and though it does give the impression of improvement, don't let anybody fool you. It will never be anywhere nearly effective and efficient as a true full working two stage trigger.
It would be years later before Steve-in NC would eventually come up with the concept of what it would take to make the Theo ben type trigger a truly functional full time working two stage trigger. And it certainly wasn’t by “just thought it up†sticking a bushing on the Fat Pin and pulling out the trigger return spring.
