I have used both 777 and Black horn 209 powders with SST bullets. You'll have to try different loads and bullets to see what your gun likes. The biggest thing is to do everything the same thing every time. CVAs are very good rifles.
First I will point out that if you're going to hunt in the west some states have special rules regarding muzzys in muzzy season. Colorado for instance no scope, no pellets only loose powder and no sabots.
As for powder I am intrigued by Blackhorn 209 but my older CVA requires I modify the breech plug and I haven't gotten around to it. I'm also a little lazy because I don't hunt it that much so I just use 777 pellets. Two 50 gr. pellets do just fine. 3 has not performed any better. Groups actually open up a bit. I am guessing your gun is new enough it has the finger removable breech plug. If this is the case you need to get the special plug they make for BH 209 for reliable ignition.
As for bullets you need to try some different ones but I like Barnes. I shoot 250 grains but have been researching recently and there looks to be no reason not to be shooting bullets in the 290 to 300 grain range. I will say stay away from the Shockwaves and SST's. It looks like they are also packaged for Traditions now too under their name. They are all the same bullet, SST's. They are very accurate but will leave you wanting for expansion out of your gun. They just leave a through and through with ne expansion and poor blood trails. The web is full of people with the same story and I have seen it first hand many times. I have shot them into all kinds of things and recovered with no bullet deformation at all.
Do a little web surfing and get some ideas but you'll have to do some work yourself to find what works best.
My favorite load is a 300 gr Hornady XTP mag ahead of 100 grains of Triple Seven. Anything in the way had better duck! I have only used on deer and black bear (and never had a tracking job) but would not hesitate to also use on elk inside 125 yards.
The 240 XTPs give a little extra range, maybe 150, and are probably great for pronghorn but I feel would be on the light side for elk, given the better 300 grain option.
The non-mag versions of the XTP are also fine for deer sized game but are IMO too lightly constructed for elk, you will have jacket separation and over-expansion on close shots at bigger game.
As stated above, regs vary and scope and sabots may not be legal everywhere, such as CO. For those situations, No Excuses has some great options for conicals, just match them up properly to your rate of twist so you stabilize properly.
I have a wolf, optima and a Thompson. We shoot Hornsby 240 grain XTP with 100 grains of 777 pellets. Dam good combo.
I used to shoot the SST. I never had a problem pushing it with 100 grains. For kids when they were young we would use 50 grains. They didn’t perform great so I just switched everything to the XTP. I haven’t shot much over 100 yards in a long time.
I had an all lead 180 grain bullet I used to use it was accurate and deadly and they quite making them.
I have a wolf i use to shoot the power belts. Now i shot the 250. Grn SST with three 50 gr pellets. I have taken 3 deer at 200 yards the most one ran was mayde 10 yards. I would hunt any thing with that load.