Percentage vs dollar?

I remember reloading 12ga (not that long ago). We could save about $1 a box. That was ~25% at the time. Times 20 (for a REAL Case) is $20.

Even with a progressive $20 saving on 20 boxes (500 rnds) takes zeal.

I saw 6.5 Creed Norma on sale for less than buying new components (including norma cases)

but I still reload.

I got into reloading for various reasons but the primary reason was that you cannot simply go out and buy any black powder express ammunition and certainly not 461 Gibbs or the various 500/450s or 360s.
Also, most Rook rifle ammunition hasn't been produced for fifty years or more so the ONLY way to crack that nut is casting, forming brass and reloading on your own.
Then, add in the bullet swaging and paper patching for the match rifles and BPE rifles and you're really headed away from the retail suppliers.

I've spent thousands of dollars on all of my equipment and supplies but I'd think that I would have had to spend five to ten times that to build up a supply of custom made ammunition for the rifles I prefer to collect.
And what fun is in collecting rifles you never shoot?

In our somewhat regulated state, special storage arrangements are needed if you want to keep more than 15 guns in one house. However, if a gun is old and no factory-made ammo is available for it, you don't have to register or even count it.

So, my buddy has a separate cupboard full of old Martini .577/.450 and Snider rifles and carbines, for which he reloads. Trouble is some bright spark over here is going to start making factory .577/.450 ammo, meaning my mate will then have to jump through all the hoops.

Considering the wide variations in bore sizes, it's hard to see this new ammo working well for everyone.