FX Dreamline Classic. Upgrades and tune suggestions.

I have the current version of the .25 cal dreamline tactical w/480cc carbon fiber bottle. I've made the following upgrade to the gun: changed out both gauges for the huma air gauges as I found the fx ones to be way off. Aprox. $50 for a set of two gauges. For close range hunting, using the stx superior barrel (1:24 twist), I can shoot jsb hades 26.54 gr. pellets very accurately at 910 fps (one hole groups at 40yds), or 48.8 fpe at the barrel. This tune is based on 120 bar on the regulator, using the factory hammer spring tension and HS wheel set on 23. Using slugs, my maximum power is achieved with regulator set slightly less than 150 bar (call it 148), hammer spring tension adjusted to maximum and hammer spring wheel set on 23. Best accuracy was with NSA 29.5 slugs with HS wheel set on 21 and fps of 921. These slugs will consistently shoot a 1/2" group at 40 yds. I just purchased the stx superior barrel 1:18 twist liner ( i.e. heavy barrel), and am just beginning to shoot additional weight slugs to see what accuracy can be achieved. With the standard 1:24 twist superior barrel, the only slugs i could get to group consistently were the NSA 29.5 slugs. How this info helps.