ORIGINAL: srwshooter
sidelocks do not have a sealed breech ,you may never see a crud ring in one .
I have used T-7 in my T/C NewEnglander and actually do get a crud ring with conicals. Not bad, but I can feel it when I swab between shots.
BTW - The T-7 shoots well and is decent on accuracy out of the sidelock, but there is an occasional hang-fire.