Couple more thoughts based on subsequent posts:
I am using my old Lee dies (long installed in my LCT that cranked out tens of thousands of rounds) in my new-to-me Dillon 650. The biggest challenge is that the dies are short compared to Dillon's very tall toolhead, and Dillon's tall dies. I was unable to get all the Lee dies down far enough with the Lee lock rings installed... I just ran out of threads at the top of the sizing/decapping die and, IIRC, the seating die (or maybe it was the FCD). One workaround is to install the Lee lock rings up from the bottom of the toolhead. The other solution, which I ended up adopting, was just to get some Dillon lock rings. Dillon lock rings are very thin, and the amount of threading they take up on the die is small enough to the get the dies into position.
Biggest problem with this approach is that the Dillon lock rings lack an o-ring (like the Lees) or the Hornady set-screw or any other mechanism. They only lock by being tightened between the press and die very firmly. I was used to being able to just install and remove dies with the lock rings never moving (thanks to the o-ring or set-screw) and without any use of tools at all. But once the die is removed from the toolhead, a Dillon locking ring spins very freely and will not hold its setting. I never bothered with loading up a bunch of different turret rings for my LCT because installation of dies was so easy, but if I were trying to load multiple calibers on the 650, I would definitely want separate toolheads... otherwise, you'll have to adjust the dies every time.
- Short version: You can make Lee dies work in a Dillon, but you will need a lock-ring solution. Order some Dillon lock rings (which, unlike most Smurf-flavored things, are not super expensive).
Next issue: Caliber changeovers. I currently only load my USPSA gamer load on my Dillon. That round counts for 90+% of my shooting volume, so leaving the Dillon set up for that full time is sensible. I continue to do everything else (roughly 10 other calibers) on my LCT. Since everything else is consumed in much smaller volumes, doing a run of 50 to 200 rounds is not worth changing over the Dillon (much less the expense of the caliber conversion parts - which are NOT the dies).
But for higher volume reloading, the difference in speed is
amazing. It is
so fast and effortless to crank out rounds on the Dillon compared to the LCT (which I was pretty adept at running quickly). They are not comparable. I can build an inventory of rounds in just a couple of hours that would previously have taken me all weekend. Or, more directly, I can crank out replacements for whatever shooting I'm doing so painlessly that there is no longer any reloading-time barrier to my shooting. I shoot however much I want/can afford/can get to... no longer does the hassle/time of making ammo have any role in the calculus. Burning through 500 rounds of ammo in a practice session used to be a very bittersweet feeling, because I could see all the time at the LCT just going up in smoke. The 650 eliminates that feeling.
- Short version: If you get a 650, you won't ditch your LCT. But you will want to ditch it for high-volume stuff.