I think this deserves some field work. Push some bullets and sabots through and then see if they shoot the same as an un-pushed sabot and bullet.

Dave,
did you read my above comment on this?
Also I forgot to mention that the loads mostly that I had saved that were used came out of my Accura. I load on a clean ballre and they load easy, the loads that I had there were pushed out of my accura were used in my buddys Triumph. My buddys Triumph has a tight barrel. The Bullets and Sabots I used on his MLer fit much tighter and were harder to load, so I figured even though there were (slight) riflong groves in the sabots from my Accura that it should'nt have mattered much as when we loaded them down the tighter fitting bore of his Triumph that the Sabots would have made new groves from the Trimph's rifling as it was a much tighter fit.
Either way if this did or did not make a difference they still shot as good as the new ones.
(BP)

I reuse the powder pellets and the sabbot..I was taught that after the cleaning to take a shotgun patch { Lightly oiled} and stick in the end of the muzzle.This keeps the humidity out.

I dont re-use the Powder, there's just something about lose powder, I cant explain, it's probably fine but I dont, Pellets I might. I always store my MLer's with a Lighty Oiled Patch of MX BC in the end of the Bore along with a good coating of MX BC in the Barrel.
For me personally I always use New