Quote Originally Posted by 18 Wheeler View Post
There are different versions of the FWB150 foresight. Some are secured using a Phillips headed bolt, whilst the one on mine uses a pin with wedge machined on the underside, this slides into a groove machined near the muzzle and retains the foresight assembly.

I think the pin model is earlier. Without the groove it wouldn't be possible to use this version on a plain barrel? Not having seen the screw version I'm not sure if they are interchangeable, but something to consider to stop you buying an unsuitable part.

It is the 'pin' version that I am looking for, the pin locates into a groove cut into the top of the barrel.