The 625is finiky about primers ,I installed a.008 longer 1 while workin mine to resolve the misfire issues & used only federal primers.
For cleanin the barrel I turned from the lewis kit & use EDs RED & choreboy copper pot scrubber wrapped around a brush it cleans crude, lead ,& carbon in even the forcin cone in just a few passes !
I tried a copper solvent but went back with EDs RED it does`nt attack my choreboy & it does an excellent job on lead in conjunction with the choreboy !
Wrap enuff to make a tite fit & make a few passes & the scrubbin is over!!
Carry a magnet with ya so ya don`t buy copper coated steel !
