Brian,
I presume you are refering to a Lyman Spartan press, which Lyman no longer makes and does not have parts for if something breaks. Yes, to answer your question, you can load any calibers on the Spartan. It is a "C" press so under great stress it might exhibit a small amount of spring. However, it is obsolete, and there are better presses available. The question you might want to ask is why would someone use a push mower when newer, more efficient power mowers are available. If it is a second press, I would say go for it but if it is going to be your primary press, I would suggest you look at other options.