It was a brand new gun when I bought it, so nobody has messed with the foresight before. I think the problem lies with the bushing wearing for some reason, thus giving the retaining pin room to move to work itself loose. I used a s/steel rod, rubbed down to the correct dia and tapped it into the hole. I've since put 1000+ rounds thru it and it seem fine.
I saw that the bushing doesn't even feature in the spare parts list or expanded parts diagram. Surely an oversight even if it doesn't break very often. There're probably another 20 bits that are included that will also never need replacing!
On the subject of the fore-sight, I find it difficult to pick up in bad light. The white spot, (even enhanced with some typwriter correcting fluid!) is not as obvious as some other guns I've fired. Para Ord 45 for example, which has a nice orange flourescent add-on. Fancy. Anything equivalent for the Combat?
Thanks, Pete