I shoot production which is limited to 10 rounds in the mag. Since you're just starting out and it's the end of the season, shoot limited. Load your mags to full capacity and aim carefully. 3 mags would give you ?46? Rounds to complete a~32 round course. That should work.
I can now place who you are. If you don't want to buy gear, I have a S&W M&P full size and holster/ mags/ mag pouches you could use. Or you could just use the mag pouches and your gun.
Paul