AGDEXTER, lubrication of any type is unnecessary with plastic sabot bullets. For one thing, the rifling is fairly shallow, and shallow rifling works better with low-to-no lube. The sabot is what grabs the rifling, and the plastic, since it's oil-based, needs no further lubricant.
Whatever powder you use, genuine BP, P'dex, 777, etc., is just the propellant. I used to shoot some high-power rifle, and lubrication in the bore is a huge problem with accuracy. The T/C Encore is really a modern firearm, even though people put bp or variants through it.