Here's a thought. Join your local Militia infantry or armoured unit and you will have a good chance of shooting a Browning .50 cal MG for free. There's nothing quite like hearing the leopard cough of the big M2 and seeing the big trace go downrange, all for free of course.
I don't know if the reserves get to train on the .50 cal sniper rifles, but once you are in uniform there's always a possibility of this happening.
As a bonus you will also learn some other useful skills, like making your bed on a regular basis and improving your personal dress and grooming.
