I haven't bought a gun cause I happened to have the brass, but I have bought brass, bullets, and dies so that I HAD to buy the gun.
Got my .22 Hornet and .358 Winchester that way.
I knew I wanted the 77/22 Hornet, but didn't have the money for the rifle at the time. So, I started buying components and dies, a little each paycheck, so that I would have to buy the gun in order to not have wasted the money on components and dies. Didn't want to blow the gun money on something else, kinda kept myself motivated to save money for the rifle.
Did the same for my Ruger .358 Win.
I think the next brass to buy is going to be.38-55...................then I'll be forced to buy a Chiappa Little Sharps, or Browning 1885 Low Wall.