I have been reloading for my 460 XVR for over 2 yrs, maybe 3. My gun is the 8-3/8" version with the "gain twist" rifleing. That's important. I also have a Burris 2x7 scope. That's real important.
Hornady's website has the load data for the FTX.
My accurate load is with the 200 gr FTX bullet, 50.5 gr H-110 and LRM primer. I tried using standard LR primers, but I got somewhat better accuracy with the LRM's. I'm talking about 1/2" better groups at 50 yds and 1" better at 100 yds. I chrono'd that load at around 2,200fps. When the conditions are right, 5 shot, 3" groups at 100 yds is very douable. Five shot, ragged hole groups at 50yds is also douable. Hornady's data goes to more than 50.5 gr, but that is where I stopped.
My gun does not shoot lead worth a crap at any thing better that 25yds, but then I've only used Trail Boss powder with the lead bullets.
I had some success with 300 gr Speer bullets meant for the 454/460 velocities, but the best accuracy was around 4" groups at 50 yds. My take on that is the "gain twist rifleing" will not stabilize a heavy bullet. That would make a great short range, big hog load.
Have fun with those 200 gr FTX bullets with compressed loads of H-110. I will warn you NOT to shoot that gun without hearing protection. I wear plugs and muffs. The compensator will direct the blast back at you. It is like being hit in the face with a pillow.
I once shot mine with the muffs (no plugs) on my head and above my ears not covering my ears. I will never recover from that blast. I got distracted and didn't place the muffs back over my ears before I shot. It was like an icepick was jabbed through my left ear.
I've made a couple of shots with only plugs. That's not fun. The muffs I use amplify sound and then shuts off the gun blast. They work great alos with wearing plugs. You can amplify the sound to carry on a conversation, and a a gun blast the world goes kind of quiet.
Have fun