Rsilvers wrote:
With the D-fender, do you leave the other insert in place? And does it matter if the other insert if black or blue?
And also, does the new black D-Fender have the same properties as the older blue one?
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AFAIK, the insert is an attempt to do what the D-Fender does, in a different way, so I think having both would be a duplication, and possibly not good. I never tried shooting with both of those items in place.
The black D-Fender and the older blue D-Fender are the same material, just different colors. All of them come black now.
Regarding the O-ring "replacements" instead of D-Fenders, the D-Fender is "wedge-shaped" in profile, and is designed to provide the needed shape that interacts with the tension of the spring being stronger on one side than another(due to the inherent forces provided by a coil). It does not get "squashed" like the O-ring does. When the O-ring gets squashed, it ties up the gun. The D-Fender has never had a malfunction due to being "squashed" like the O-ring does. I can't believe that with a $10k M16, a $12.95(shipped) part that enhances reliability is even a cost issue. It's not like there's a question about it. It has an outstanding reliability and performance record. That being said, if you want to put the $1 O-ring into your $10k M16, it's fine with me. But, let it be said that I warned about what will happen. We tested these things, and if the wedge shape wasn't needed, we wouldn't have gone to the trouble of making it that way. We made it that way, because we saw in testing what happened when it was "just an O-ring". Our designs are patented, and that's why you see all these other "methods" of improving extractors that are NOT like ours.