Just like reloading, getting started casting *can* be quite an investment if you buy into the hype that you need to buy lots of equipment, but it can also be accomplished 'on the cheap'. Check out
this page as an example of a very straightforward yet simple casting/reloading option. I also can't recommend the "
CastBoolits" website enough; you're unlikely to find a better source of information for casting your own, & you may even be able to find some members willing to send you some of their own cast bullets to test with.
I knew I wanted to start casting/reloading my own bullets when I decided to start reloading, so I jumped in with both feet & immediately started reloading
these for my .40 S&W & had no problems. Since then, I've seen some comments suggesting thats maybe not the best caliber to start reloading for, but I'm a noob & didn't know it was supposed to be difficult
ALL of my lead is recycled range lead; I spend quite a bit of my range time picking up all the empty brass everyone leaves behind, & picking up fired bullets from the backstop (jacketed or plain lead, doesn't matter). Bring that home & melt it down over a propane burner & pour that into an ingot mold of some sort (I just use an old 12-hole muffin tin). Then, when you're ready to actually cast some projectiles, just drop a few ingots into your pot & wait for them to melt, then start casting!
To my surprise, I've found casting & reloading to be virtually as enjoyable as actually shooting, & find it very satisfying to know that you can create ammunition to rival factory-produced rounds at literally a tiny fraction of retail costs.
With my free brass/lead range pickups the only expenses per round are primer & powder costs (+propane/electricity, & my time, which would have otherwise been spent in front of the computer or boob-tube, so I don't really factor those in); nothing quite like turning out loaded rounds at ~$0.05 each (vs ~$0.30-$0.40 each for the CHEAP retail ammo). The per-round cost difference has already more than paid for my equipment costs, but don't expect SAVE any money in the long run... You're just going to shoot a LOT more for the same amount you'd have spent on factory ammo....
Happy shooting!