Anti-Walk Pins

[thirtydaZe]

Necessary or not?

I have to say, i was a bit surprised how easily my hammer and trigger pins slipped into place.  In fact i just pushed the trigger pin in with my fingers.

[FarmerRick]

If everything went together as it should, the hammer springs and the little spring in the center of the hammer pivot hole should keep the pins in place. 

That said, I am in the process of adding anti-walk pins to a couple of my more "serious use" AR15s.

[Randy]

Here are some from KNS http://www.knsprecisioninc.com/gun-parts-and-accessories/trigger-hammer-pins.html

[thirtydaZe]

Right on.  I guess it all seems to be together fine, beauty part is it can be added later.

[shooter]

I have owned many different AR types in the last 40 years, I have never had a pin walk or move a bit, I don't think its a problem at all

[David Hineline]

If assembled properly it is not needed. Once in a great while a pin will walk because it broke.