Assuming you've saved your brass, you can get blemished bullets for less than $20 per 100, let's say $5 per hundred for the primers, and about $22 for a pound of powder. You'll have some powder left over, but this would come to about $.47 per round. That's less than $10 per box.
The cool thing about reloading is that you'd spend the same to reload 100 rounds of the 300 Holland and Holland or the 300 Savage!!! That's where you'll really save.
44 Magnum ammo will be cheaper, as you can choose cast bullets which are less expensive, and a pound of powder will last a loooooong time.
Theoretically, you can save money reloading, but I don't know anyone who ever has. We all just shoot a lot more. The great thing about reloading is that your imagination is the limit on what you can shoot in your gun. You can tailor a load for optimum performance, tighter groups, etc. I've even loaded crushed walnut hulls in a 38 special for shooting bore bees. You can't buy those in the store.
What have you got that's chambered for 300 Savage? A 99 perhaps?