It slide over the barrel with muzzle flush to the open end.So the fake supressor you have/linked to, slide right over the barrel? Its a do it yourself type of install?
Thanks
You can intall it yourself using common electrical tape to make up the barrel to 0.75" inner diameter of the tube.
or you can thread the barrel to accept an adapter with set screws.
Details: m4-fake suppresor
While a thread barrel and adapter is a more elegance way to go I find that electrical tape wrapped barrel twice provide thickness and friction enough to hold it in place well.
This is my first version of a 15-22.
