As Jim so correctly points out, it depends on a number of factors other
than the direct cost of components.
For example: Setting-up costs. I suggest there's nothing wrong with buying good secondhand reloading gear. Do you have any friends who are "into" reloading? Better yet, are you a gun club member?
I bought my RCBS Rockchucker press from a fellow club member -- $125AUD (about $75US). On the spur of the moment, he included (in the price): lube pad; reloading manuals; Qnetics (?) powder thrower; powder trickler; case trimmer; deburrer; primer pocket cleaner; bullet tray and case; and about 500 bullets of different weights!! He also sold me a set of scales for a further $50AUD ($35US).
I only reload my Hornet at present, so let's consider that.
Factory ammo here is approx:
$1.10AUD a round ($22 for 20).
Reloading component costs are (per unit):
Winchester brass -- 28 cents
Hornady 40 gr -- 28 cents
Powder -- 5 cents
Primer -- 4 cents
TOTAL -- 65 cents
But of course, you don't buy new brass every time, so the costs diminish with the more times you use the same brass. And I could save significant amounts of money by buying "generic" projectiles (used in .22 WMR).
The best estimate (taking case life into account) I can make is I save at least 60-65%
on every round I fire. I only fire around 500 rounds a year, so I'm saving myself about $375 a year in ammo.
As for my time -- well, it's fun and I find it relaxing. If I'm not doing anything critical (say just decapping or tumbling), I have a small B/W TV set at my bench, so I don't
have to watch Seinfeld or Mad About You or The Nanny ....
Give it a try -- when you put your first rounds downrange -- and they go "bang" like they're supposed to and
you get a better group than factory ammo -- it's worth every second!!