As I said, I assume the X is the same rail spec as the Tac Ops, Scorpion and whatever else SIG might make. I'm going to say SIG sees this as the standard others should be using.
Just off the top of my head I know the following make (or have made) railed frames. How many of these are the same spec as the Springfield?
Colt
SIG
Caspian
JEM
Tisas
Taurus
Kimber
Ruger
STI
Dan Wesson
It would make some sense that holster makers would use Springfield as sort of the standard. I could also see Kimber as the other common railed gun. Maybe the Springfield and Kimber share a rail already?
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