Do you alreadyhave capacity to reload? Press, etc. If yes, the biggest expense is out of the way. If no, then you'll need to invest up front, and your ROI will be longer.
I didn't start reloading for cost or accuracy - I just wanted to have ammo on hand when I wanted it. I run hot and cold with some calibers - last spring I think I ran through close to 2 thousand .303 rounds (I had a short-lived obsession with mad minutes, and beating my own scores). By about June, something else became the shiny object and I didn't pick up a .303 again for donks. You never know when factory rounds in any caliber just might stop being widely stocked. I could'nt imagine a worse feeling than "I'm going to go shoot my XYZ today, let's go get some ammo!" and then not being able to find any.
Quickly, reloading then became fun - you can be a little mad scientist about it, and brew up your own (appropriate) loads, and for some calibers, I have several different loads for the same gun. It also became a little therapeutic I think. I find myself at the press sometimes when I just need some quiet time.
Do I spend less with reloading? No. But I do pull the trigger more.
Off the cuff, here is my estimate for starting with nothing and having the ability to have a few 100 .303 rounds made at home:
- Lee Anniversary kit: $150 (don't believe the hype, it makes great ammo)
- .303 die set: $35
- 1lb of your powder of choice: $35
- a manual: $30
- 100 new PRVI .303 cases: $90
- 100 large rifle primers: $7
- 200 cast projectiles: $40
Depending on circumstance and choice, you may be higher or lower on those numbers, but they are fairly average. You'll get like 200ish average rounds from the tin of powder. The reloading kit, manual, and die set are one-time investments. The brass, if you marry it to your gun correctly, will give you 10 or more loads.
If you don't want to invest in that, then you'll invest in expensive factory ammo. Either way you will be taking your wallet out, so just choose whatever you see more value in.