He snaps one off!

I happened to hear this expression 'snap one off' from this blog,
whose meaning is, if the blogger is not mistaken, 'jerk off'.

However, some argue that the meaning of it is, in this context,
just tearing apart the magazine, not masturbation.

The most reliable way to confirm this is turning to native speakers, I concluded.
Personally, I believe the blogger is correct.
Not sure though.

Could you please check this out and verify the meaning of 'snap one off' here?

http://blog.naver.com/creatiger/220304843103

Thank you in advance.