For less than $3 you can't beat this..... I calibrated it against known weights and it was remarkably accurate. Has a lot of nice features too like "hold" of value, etc.
http://www.ebay.com/itm/New-20g-40K...=US_Pocket_Digital_Scales&hash=item27d936736b
If you repackage this and call it a "gun" part....or better yet, a "tactical" part....you can command over $60 for this like Lyman does, for essentially the same thing--->
http://www.amazon.com/Lyman-Electro...5138&sr=8-1&keywords=lyman+trigger+pull+gauge


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http://www.ebay.com/itm/New-20g-40K...=US_Pocket_Digital_Scales&hash=item27d936736b
If you repackage this and call it a "gun" part....or better yet, a "tactical" part....you can command over $60 for this like Lyman does, for essentially the same thing--->
http://www.amazon.com/Lyman-Electro...5138&sr=8-1&keywords=lyman+trigger+pull+gauge
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