Unless i am mistaking your meaning, one can't put a bearing on the firing pin side (muzzle end) of the spring because the straight piece on the end of the spring is needed to go down the firing pin slot and capture the cocking piece pin shaft.
However, on the breech end, smoothing the spring end and the inside of the BAS (if there is a burr) helps a lot and is not hard. A thrust bearing that goes around the firing pin shaft shaft helps even more.