Last year tuned my RE .177 - standard clean/polish, new seals and new guide/top-hat. I retained the existing spring but collapsed/polished both ends at it had just been chopped and unfinished. After bedding in, can only get power to around 10 lbs/ft and that’s with around 30 mm pre-load – which seems too much pre-load.

Therefore, decided to replace the original spring as it is quite short - after collapsing it is 200 mm. The Titan #1 is the same ID/OD and similar gauge but is 280 mm long.

Before starting a potentially lengthy session of cut/collapse trial and error, I wondered if anyone knows the approximate suitable length for this spring & rifle? I know it depends on lots of factors and will need fine tuning but a general guide for cutting length would be helpful.