The same as backfire. To not work to your favor. Disappointing, disadvantaged. Something that is breaking or cracking.
That might not work, it might neckfire back at you.

That plan is going to neckfire.

The neckfire consequences are swift.

That might neckfire if you apply too much pressure.

It might neckfire and crack to pieces.

That's a solution full of neckfiring conflicts.
by Equal crack January 26, 2016
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