Mainspring pivot pin seating procedure

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Bullseye
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Mainspring pivot pin seating procedure

Post by Bullseye » Mon Jun 15, 2009 11:19 am

Before you go hitting the bolt stop pin hard you should check to see that the bolt stop pivot pin has not wandered out of the mainspring housing. If it does it will act like a stop and prevent the mainspring from being extracted from the receiver and frame. This is especially true if you have a polymer frame, as hitting the bolt stop hard will cause the pin to tear out material at the backside of the frame. To do this check procedure, you'll need a feeler gauge to slide in between the housing and the frame. If it hits something on one side and not the other of the housing, the pin has walked out of the housing and and is protruding to one side.

You will have to tap with a mallet on the opposite side of the frame and check frequently to reseat that pivot pin. Another way to move the pin back into the mainspring housing is to use the pistol like a mallet and strike it sideways lightly on a block of wood. Of course, you want to strike the side of the frame opposite of the pin protrusion to reseat the pin. The process works a lot like one of those kinetic bullet pullers. Also you must check frequently to ensure that the pin has not ventured too far and is sticking out of the other side of the housing.

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Once removed you may need to restake that pivot pin to prevent this from happening again. You'll need a pointed punch and stake a heavy dimple into both ends of the pin.

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