I have Redding dies because RCBS didn't/doesn't make dies (if memory serves.) I also have a Wilson drop-in case gauge. Be very careful with the roll crimp or you will buckle the shoulder trying to put the crimp in... I have a separate crimp die now, and that helps. The Lee FCD does not go down far enough to effectively work, at least in my experience.
As mentioned, I use Montana's RCBS 200grn cast bullet w/gas checks in my carbine. I was shooting it out to 900yds this past summer with a Williams receiver peep, it worked very well with IMR3031. Velocity with IMR3031 was actually higher than with H4831, because of the shorter barrel, I believe; the muzzle blast from the H4831 loads was substantial. From what I have learned, powders in the IMR3031-IMR4064 range would work best with 200grn bullets, I'd save the H4831 for the 250grn bullets.
If you shoot cast, you will have to bell the case mouths slightly or risk crushing the mouth, or shaving lead. I improvised and used my .380 bell die and just manually bumped the mouth open to seat my cast bullets. Not the most exact method, but it worked.
Like others have mentioned, if you want to load any quantity of brass, you need to get it now. Once that run is sold out, it's very unlikely we will see any for a while. I lucked out, I happened on 4 boxes of factory ammo for about the same price Midway is asking for new brass... but that was a bolt out of the blue, I didn't even know 4 boxes of factory existed, still.
I had a pretty good quantity of vintage factory ammo at one time, (pre-70's) and, like the other poster mentioned, reliability with it was very spotty. I wound up just pulling the bullets and processing the brass as once-fired. It seems like the older ammo was all stored in the tractor shed or in the basement, I had to scrap some of the cases because of corrosion spots.
OP, you are welcome to PM me directly if you have specific questions, I have some reloading data I can share, and if you are jammed up for components I might be able to help.