There are gun ranges, but not that many.
But finding one of these to fire at a range probably not too hard, however, being that the price point is 15k to buy one, the rental price is pretty high, 5 rounds of .50 costs $30 at the one in Vancouver.
I don't really understand the attraction to firing these things so much...ammo isn't cheap, makes for expensive hobby. Knowing how, sure, but shooting at a paper target for sport...eh.
Specially with a .50...