I’ve had a Leshiy for a long time. Basically since the thing was invented. Even though I shoot .22 and not .25, I can still tell you what I’ve learned. It will send a pellet at an amazing speed, but it comes at a cost. That’s why even with my .22, I’m now almost committed to the 350mm barrel. As you tune the gun, you will feel when the gun starts getting a little jumpy. I would advise that you set your gun right below when the gun gets spastic. You will shoot it better. Myself, I wanted to be around 800fps with my .22. It would do it no problem with the 250mm barrel but the gun was not easy to shoot. It felt like a tuned springer. The 350mm barrel let me set the reg lower and have less hammer strike to hit the 800fps range and not have a jumpy gun. With your .25, just start at 110b and see what it gives you when you hit the peak velocity and back it off 2 clicks. The beauty of the Leshiy tuning process of starting off at 1 or 2 clicks is you will feel how sweet the gun is until you click to a certain point and feel it getting angry. With the .22, it’s around 700fps. But I can live with the gun getting a little more active at 800fps with the 350mm. It’s nothing compared to how active it was with the 250mm at 800fps.