Yeah bills a good egg, setting up my reg, valve spring n hammer spring today, I cant hit that sweat spot just right, cut one hammer spring a bit short, the second one legal, just... the difference between spring return is horrendous, cut quartet coil, it'll drop .25 ft lbs, cut another 1/4 it'll drop .5ft lbs, another quarter .75 ft lbs... I want her bang on 10.5ft lbs so shes under 12 with Bisley magnums
I use Bill’s hammer springs, the lightest, as all my builds are low power for my limited 25-yard home range.
My transfer ports are also the Gen 1 Crosman Challenger’s and from the 1701P’s/1720T’s.
I have about the same Disco/2260 build as yours, but I am a big fan of Cothran’s parts, hence….
This one has a 14.6” Lothar Walther .177 barrel: