Good stuff on the sabots Yellowriver. Sabots can tell a lot so picking up the spent plastic can be beneficial, plus it helps keep the range free of debris.
Personally I shoot all year and have yet to experience any plastic fouling regardless of how warm the air is or how hard I push the load. Honestly I think that todays sabots from Harvester or MMP are made of plastics that stand up to the rigors of the 209 powder and T7 products, both much hotter than any of the other BPs or subs. If people are seeing sabot shedding in the barrels they are probably dealing with a bore or rifling issue, both of which can be pretty much remedied with some JB Bore Paste and an hour scrubbing it thru the barrel. I always use a solvent to clean the barrel when shooting the 209 powder, never anything water-borne or made with water.
Weighing the powder and cooling the barrel are really a must on the bench if one wants the best accuracy. And definitely take your time or make certain you have enough time to make the range time worthwhile. Six quick shots really won’t tell much. About the only thing I’d add is that before you hunt a bench sighted gun, take a few shots both off-hand and using a roofing post. It has been suggested that there is a difference between the zero of a bench sighted gun with the rod out to use for loading and the same gun used with the rod in place under the barrel, often by two or three inches. So if you shoot using a rest under the forearm of your gun with the rod out of it at the range, you’ll want to do the same in the blind where the rest is. I leave the rod in the gun and use a range rod for loading. And when you and the gun are in sync off the bench be sure to take a couple shots using an upright rest of some sort and a couple off-hand just to avoid any surprises.