If your only going to load for those two rounds, and stick to one or two components for them, then you will pay for your equipment in the first year, depending on how much your shooting. Actually, if you load your own bullet, work up the best load for each of your rifles, then end up taking the best head of game of your life, using your bullet, then you just effectively paid off your equipment.
Pretty much, other than that it is as the others mentioned. Once you get into it, you will find that it is very enjoyable to load your own ammo, and experiment with the different bullets out there. If you only shoot three or four boxes of shells a year, it really isn't worth it. If you shoot that many in a weekend or a month, then you can absorb your initial cost in short time.
If your looking into it, I would suggest picking up one of the complete starter kits like RCBS offers. Pick up a couple of manuals to go with it. Then after reading the manuals you will have a better idea of what you want your initial load to be. I would suggest picking out one or two powders at first that will give you the best bang for your buck. In other words after reading through the manuals, you will find that one or two powders will be decent load for both calibers. Use this sort of set up for your initial outlay of fund. Say use the same powder, and bullets. This will at least keep you from opening that big can of worms until you have some experience. You can get some really good loads for say a 165 - 180 gr bullets which will work just fine in either of those calibers. If you shoot that Whby. a lot, it won't take you too long at all to pay for your equipment. /ubbthreads/images/graemlins/grin.gif
Read up on everything and ask questions before you buy, and you will be fine.