Quote Originally Posted by Garvin View Post
I see WG is selling single spring kits for the 300S that it is calling 'stark' (ie extra powerful), for export. It would be interesting to see what power they develop.

Maccari in the US sells a single 300S spring that makes more power than the standard double springs. I vaguely remember reading they produce 50fps or so more, but not more than that, without making the firing cycle any harsher.

Alistair (Hsing-ee) fitted a Maccari spring into one of my FWB 150s many years ago and it was a bit more powerful than before, but I think he had a tough time getting it into the cylinder.
I don't think I managed to get the Maccari spring in, the one that fitted and is in there is a slightly shortened HW50 Mk I spring (I think), a couple of coils taken off. I think it was doing 7 fpe which is not bad for 'one of they target riffles'.