Rifle rounds, in general. On my SS press, reloading pistol feels a little inefficient.
223 Remmy in particular, for many reasons. It's the only caliber I have a 6 cavity mold for, and the caliber for which I have the most cases. I was gifted 1000 truly OF'd LC by a friend that I am not even close to touching, yet. Sizing force of lubed 223 is less than most pistol calibers. And I have got the whole process so streamlined with an M die, no inside chamfering, less and faster* trimming, and a slicked up powder measure, that I'm loading it just as fast as I ever loaded jacketed.
Plus, whenever I load a 7mm-08 or a pistol rd, it always crosses my mind how many .223 boolits I could have made with the same amount of lead. At least it's the only caliber I use lino for, else it would drive me to fits shooting 230 gr 45 ACP.
*Finally figured out how to use the Zip trim chuck to its full potential. I must be slow, because I've been locking the case into the Zip chuck by hand for over a year, instead of zipping it open/closed with the drill while holding the case on there with a fingertip.
Between Zip chuck mastery and less chamfering, trimming is so fast it's nearly painless. It's easier to trim an entire batch when due, than to measure and separate, now. I have also imagined a system where I hopefully don't have to use the calipers, anymore, at all. The plan is while loading an older batch, I can identify the ones that need trimming by where/how the crimp ends up, and put those together for a dedicated shoot n trim session when I have enough of them. Which I can afford to do, since I have so many cases.