duggy wrote:Why aren't you keeping this pin? (I have been curious about how well these work).
I originally bought it to use with my POF billet lower, but it would not fit correctly due to the additional material around the takedown pin hole. The portion that rotates would bind on the receiver. I do not need it with the current lower I am running. I never set it up, so I can't say how well it will work. I think it will work well as long as you take the time to set it up correctly. I would measure the height of the takedown slot in your upper receiver with a pair of calipers, and then adjust the takedown pin so that when the collar is expanded it is the same. Measure the elongated portion (not across the section with the slot) as the colloar will expand in one direction and contract in the other.
One thing I noticed that they do not mention is if you don't align the slot in the expanding collar (copper colored piece) to face forward or toward the rear of the gun during installation, it will not expand in the correct direction to draw the receivers together. Just something to keep in mind during installation.
This pic represents an exageration of how the expanded collar would look. Notice how it is elongated vertically and narrowed horizontally, that is how you want it oriented when installed. Otherwise the fit will be looser, as it is expanding in the wrong direction.
