Not really. If I can knock a mask off, kill the pred, and defuse in less than 12 seconds, you can too.
It’s literally just match game. You need to lay your entire primary magazine and quickly swap to your secondary and continue laying into it. However, if the mask doesn’t pop off after all of that, you’re dead unless you can defuse in under 5 seconds.
Better yet, run a shotgun if you plan to attempt to defuse. It takes care of masks and the rest of the downed health rather quickly. Gives you plenty of time to defuse.