If only it was that easy....
Unfortunantly equipment is only one part of the overall equation. To buy finished bullet casting metal is expensive and you have to do very high volume to make a profit. In order to do volume you need labor besides yourself and you have to be willing to pay good wages for good help and that affects your final sales cost. You can't do this with minimum wage help.
Finding raw materaials and making your own metal in enough volume is a daunting task unto itself.
Add in FFL licence and regulations of where and how you can do this also enters into the equation.
When metal prices spiked a few years back, dozens of small and large bullet casters closed their doors never to reopen. If it was all that easy and profitable they would have come back and they haven't.
Those that have endured did so because they were able to adapt and change to the market conditions.
Then there is always the spectre of having the goverment render you null and void with a change in the law.