Quote Originally Posted by Shed tuner View Post
It's all progress Dan..

Howsabout a quick vid of it in use and some specs ?
The barrel looks shortish - 11" ? An option for 14-16" will give more efficiency.
Also when you talk about reducing the action length.... maybe also consider using the space saving for more spring room instead (helps with spring longevity and stress) as it doesn't look too long at present ?

Continued good luck on this mission !
I will get a proper video in a couple of weeks. I was going to make a floating rifle platform on a bed of ball bearings, and rig up a trigger pullerer that won't impart any rearward force.

Specs currently:
Stroke somewhere between 70-75mm
Bore = 28mm (using Diana piston seals ATM)
Weight = around 3900g, but P3 version should come down to 3600g (less than a HW35k)

The barrel is 10" .177. the plan is to do power development with this barrel, then I will know for sure that other calibres/lengths won't be a problem.

Length (not including barrel) is the same as an LGV which is about the biggest break barrel I could find (that wasn't super magnum). The aim is to get it down to HW80 length. It also saves a useful bit of weight. Good point about spring length through. I've taken most of the length off of the transfer port and the trigger block. Spring room is hovering around 200mm.

All excellent feedback, thank you