Not sure what you mean by ready at the bottom. If you mean they are a checked bullet design without the check attached, you can get a Lee sizing die (+/- $14) in 0.452 and attach the checks yourself. Expect to pay $17 and up for 1000 checks. You can get both the die and checks from Midway. If the bullets aren't a check design, you can't check them without a large expense. Hanned Line makes a tool whereby you can make checks from beer/soda cans and then attach them to an unchecked design. Start up cost for the tool is high. You might want to try a few without the checks and see what the news turns out to be. I suspect if you load them moderately, you can get by without a check. My powder of choice would be relatively fast burning (Unique or Bullseye) to bump up the bullet to fill the bore.
