I owned one. Yes, made by Hatsan and what they modeled their first 125 series rifles on. Except for cosmetics, they're the exact same rifle, so finding threads on the 125's should help you some on things to do and try with your Talon. The Talons were spring piston not gas rammed so teardown, a good cleaning and proper lubes vs the factory garbage would help greatly. Being a spring powered rifle, you can also do what we call a slot tune, which is getting a little moly paste spread along the cocking slot on that spring. It's a temporary fix but it can help a bit.
The Quattro trigger is also quite good, it's just getting that odd, backwards and up trigger pull the same every time. A good friend I've never met explained it this way and it's worked for me: Put your finger on the trigger, then slide it down so the edge of your finger is resting on the inside of the trigger guard. Now use that trigger guard as your guide and you'll get the same, repeatable trigger pull every time you shoot since it makes your finger do the up and back motion the Quattro takes.
Better quality pellets might also help with your accuracy and as mentioned, the JSB King 18.13gr pellets shot the best in mine, 770 fps 10 shot average, ES of 12, SD of 3, 23.87 fpe. If I did my part, not easy with the beast, it would shoot a hair under inch groups at 30 yards. Best place to get those if you want to try some is Trenier Airguns:
JSB Exact Jumbo Heavy.22 Cal, 18.13 Grains, Domed, 500ct, precision airgun ammunition for your shooting needs. Whether you shoot from an air rifle or pistol, 4.5mm, 5.0mm, 5.5mm caliber or larger, outdoors or indoors, from paper to knock down targets, from 10 to 100 meters, JSB offers you a wide...
www.trenierairguns.com
My Talon Magnum .22, now owned by the friend mentioned above:
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