Numrich (gunpartscorp) is one of the few places offering the barrel extension (or most of the other S&W 15-22 parts) for sale. 15-22 Barrel Extension



In the picture you can very clearly see the spot where one of the holes should be to pin the extension to the barrel.



Why would the barrel extension come without the pin holes drilled to attach the collar to the barrel? What am I missing (other than holes for the roll pins)?



I actually need this as I have an aftermarket barrel that comes without the extension included.


Do I have this drilled? Is there another way to attach the extension? Do I just find another source?

Your replacement barrel will not have a pin slot so every thing will have to be drilled together. You just need a good rigid drill press and vise or milling machine. Not a hand drill job.

I'm using the TACCOM3G Ultra Light Barrel, which does already have the pin slots.