Clip that will auto release under load?

[researcher]

First time poster.

Looking for a clip that will release under a load of ~250lbs.
Been looking at shear pins and torsion springs but wondering if something already exists.
It will be used between two ropes and will release automatically once load is hit. Something adjustable from 200lbs. to 300lbs.
would be ideal.

Any engineers out there have any ideas?
Thanks in advance

 

[scientific601]

This might be applicable: http://skyski.com/store/tech_docs/Comptech%20Sky%20Ski%20Automatic%20Release.pdf
They say it's adjustable from 100 to 800 pounds. Not sure of the resolution and guaranteed accuracy,

 

[researcher]

Wow...great find...
At the same time the price point is way too high.
Thank you for your response.