But after being dragged onto his fifth wave, the surfboard slipped out from beneath his feet - its fin slicing deep into his forehead, making contact with his skull.
With blood gushing from his scalp and only narrowly clinging to consciousness, he was rushed to hospital.
McCoy underwent an immediate CT scan where doctors cleared him of any serious damage from the board incident - before finding something far more serious.
A three centimetre tumour was located near the rear of his brain shocking everyone.
"Well I'm lucky the doctors even found this thing in my head. If it weren't for the fin cut, I never would have known the tumour was there," he told Stab Magazine.
Given the location of his tumour, removing it could leave the young Kiwi paralysed.
So he was left with two options.
Drilling inside his brain to carry out a biopsy was one possibility, carrying with it a plethora of risks including McCoy potentially losing his car licence for a year.
Alternatively, the thrill seeker could sit tight for a few months until doctors detected whether the growth was benign, or had grown in size.
If the tumour is found to have grown over time he will need to have it removed, but would also be forced to face potential paralysation.
"I've decided to just wait for now and check back in a few months. I'm trying not to think about it for the time beingm," he said.
For now, his positive outlook on life remains as strong as ever.
"I will survive this, I know it but if it had been worse and I had be given only so long to live, then at least in my short life I chased the waves I dreamed of as a grommet."
