9MM (I picked 9mm for my example as some think its not worth reloading, larger calibers generally yield more savings.)
2000 125gr LRN bullets with shipping $134.00 (actual price today from friendswoodbullet.com)
2000 small pistol primers $80.00 (figured high my cost is $30.00/1000 including tax)
2#’s powder $50.00 (figured high my cost is $22.83/lb if I buy 1# at a time including tax)
Total is $264.00 in components or $0.132 per round or $13.20 per 100 rounds
I know I can’t get 100 rounds of 9mm for under $28.00
At these figures not having to buy 2000 rounds of factory 9mm ammo you would save $296.00 more then enough to pay for A Lee Turret Press, a set of dies, and misc required tools to safely reload.
I don’t factor in the time it takes, if I wasn’t using that time to reload (which I very much enjoy) I would probably be sitting on my butt watching TV. I usually spend an hour to hour and a half 3-4 times a week reloading for my shooting needs. Every once in a while I will pull a 3-6 hour reloading marathon on the weekend to put a little stash of ammo away.
Buying powder in bulk will save money, and ordering bullets to maximize the flat rate shipping, usually 65#/$14.00 will also save money. I using FMJ bullets or platted bullets will add to your cost and lower your savings. Some people don’t like shooting lead. You have to do what you are most comfortable with. Right now I can reload 9mm for around $9.50/100 rounds and I don't have to worry about the store being out. I get a much better round for my money.
With the Lee Turret press additional calibers will only cost from $40-$90 in equipment depending on how much extra equipment you want. I like to order a turret, riser, and powder measure for each caliber so I don’t have to mess with changing things around and resetting up dies. I would rather use that time making more ammo.