Gamo cf20 mod version any information.

[gwyn]

Hello Jon,interesting findings! i thought the spring was going to be the culprit.
The barrel picture is interesting,i imagine the lead my have come from the tail ends of pellets, chopped off as they were launched into the barrel from the breech loader.
Perhaps remove a 1/2" off the tail of the barrel?
Strangest, is that until that spring went it was still an accurate shooter!
I look forward to forthcoming episodes!
Don.

[rovercoupe]

Well its been a interesting week, new chrono arrived and the fully resealed gun with chopped spring was way up on power too close for my liking so a few pennys out of the end and got it down to a nice 10.5ftlbs, smooth as silk with a delrin spring guide and virtually no preload and super easy to cock.

For reference the weak point seems to be the transfer port plastic seal which once replaced with a o ring will send the power upto the moon! Every single one has leaked out of the many i now own. Wether this was deliberate to keep the mod spec ones low i do not know.

A big thank you to all who have helped me through this saga I now have some guns to rebulid and bring back to there former glory.

[Shed tuner]

Result 😄