Once you start reloading mate you won't want to buy factory stuff.
I have great pleasure in getting 1/2"-1" groups at 100yds with ammo I have reloaded.
I use the weights of heads that I had free when I bought the rifle and if it aint broke don't fix it but then Not every rifle is the same
I would say 300 to store is ample to store.
Just send a letter in and ask.