Like others have said, don't reload just to save money. There are other rewards that come along with reloading, but the dollar return on investment is long to come.
Here's my numbers. I have more than 10,000 rounds of brass for various pistol calibers that I shoot. So my initial outlay for the reusable component cuts my 'per round' cost from about $.12 to about $.04 per shot fired.
(my example is .45acp. with 7000gns of powder per pound, 1750 rounds loaded per $20. Primers at $.02 ea. I have a stockpile of lead and linotype, but you could say $.50/lb is a good rate. Pouring my own bullets gets me 35 bullets per pound. That's $.01 ea.)
For rifle loads it's a bit different. As an example, I have some 1000 rounds of brass for 30-06. 300 or so are fireformed for my rifle. (I don't compete with this rifle. It's just for hunting. Sees maybe a hundred rounds fired in 2 years. I haven't purchased factory ammo for it in more than 15 years.) That said, the same math can be applied. 130 powder charges from a pound of powder = $.15 ea. Primers are still $.02 ea. I've got a stock pile of brass, but you can figure on $.15 ea in bulk. A box of 50 quality bullets at $18.00 runs you $.36 each. Lets just call it $.75/loaded round if you don't have your own brass, and near $.50 each if you do have your own brass. Add 10% for your .300WinMag.
I havent purchased factory ammo for years, but I can imagine that .300WinMag for a box of 20 is quite near $30? That's what? A buck fifty each?
Can you save 50% in cost per shot by reloading. Well certainly! More if you shoot pistol and do all the things that can help cut costs. For me, since I may shoot a couple hundred rounds in a week, I'm sure I'm saving -well, A LOT!
But, and now there's the equipment needed. I probably have thousands of dollars worth of reloading schtuph. Can you start out with a good beginner kit for just your two listed rifle calibers? Yup. A good RCBS Rock Chucker kit for the .300 belted magnums and that 30-30. (By the way, it's not cost effective to load for 30-30 when Wally World sells loaded cartridges for $8/box of 20 when you factor in the time.) Not just the presses and dies and primer pocket reamers and case length guages and trimmers and brass tumbler and polishing media and storage facility and gun room and gun safe and various manuals and chronograph so you know your bullets are traveling as fast as you calculated them to be and and and...
Now, I wouldn't expect you to run out and buy a Dillon version anything for what you've asked. But here's a pretty good article on Dillon's web site. (Even though I have an older Dillon press on my bench. Just down from it is that Rock Chucker for the belted magnum rifle cartridges.)
http://dillonprecision.com/reloadingsaving.cfm?dyn=1&cookieClean=1
I gotta tell ya, this can be an addictive hobby. I spend four to ten hours week in the gun room. Reloading, cleaning guns... The rewards are incredible though. Fireforming brass and measuring things just perfect by the book then 'modifying' that standard to your particular rifle to attain the most accurate offering possible on paper at the range. A 'one ragged hole' group is a very pleasing success. Then taking that same amount of knowledge and doing the same at altitude in the freezing rain to get the same results are exceptional displays of knowing the challenges of the science. Placing one of your own fired bullets, your own creation, into the heart of your chosen game for a clean humane one shot kill, or scoring a high score in a target match resulting from your own time, sweat and frustration creating accurate offerings is something only you can really appreciate.
Now, if you can quantify that with a dollar amount, please tell me. Cause' I gotta tell the wife. She doesn't understand why I bought another bullet mold last week.
-Steve