Every experienced gunsmith knows the value of an adjustable mainspring vise. Avoid scratching your mainspring. Scratches form stress marks eventually causing breakage. Our English style mainspring vise is case hardened steel, with sliding adjustment arm. Works well on both large and small locks. Made in the U.S.A.
Best practis is to draw the lock to half cock. Slip on the spring vise and clamp it to the spring. Never compress the mainspring past full cock, as this may cause failure of the spring! Gently lower the cock. The mainspring can now be easily removed. A good spring vise costs less than the first mainspring damaged by pliers! This mainspring vise will also work well to compress frizzen springs.