Daniel L. Arndt
just start with a 250 grain shockwave, Harvester SB sabot and 110 grains by volume BH209.
IBB, has recommended a very good load. Not the one I would use but a lot of people do...
The only thing I would suggest especially if you have a new Encore - is do not buy a bunch of sabots until you decide on the bullet diameter. The Harvester Short Black is an excellent sabot but in some tight bore TC barrels you may not get it down the barrel especially if you are shooting a new barrel. You might have to try the thinner 45/50 cal sabot such as the Harvester Crush Rib or the MMP HPH-3p-Ez load.
For a suggestedprojectile I would first ask, what are you hunting? and at what ranges do think you might be shooting? and then do you want to purchase a expensive (premium) bullet or would you rather shoot an less expensive bullet that will also perform very well?
His suggestion of BH-209 for a powder is also good choice it is an excellent powder but it to is very expensive. If you are an occasional shooter/hunter with a ML go for it. If you shoot as much as I do - I can not afford it - so I stay with T7, but I can get a full pound for $20 versus $30/$35 for 10 ounces.
Good luck in your hunt for the right combination - sometimes it takes a bit of time...
Biggest thing - have fun