Thread: Double grouping .... likely causes ?

Thanks for the comments and suggestions. Been down most or all of these points. I’ve narrowed down the field :
Stock is professionally bedded, including pillar bedding
Actions screws tight, torque checked before and after shooting
Same for scope screws and base. Scope is VX6
Barrel is new and shows suitable clearance with paper down the channel.

Stock is a cf job, but I also have the original bedded wooden stock it came with.
I tried fitting in this but new bbl is slightly bigger diameter so would be binding down the bbl channel.
So removed that and went back to assembling in the cf stock.
While doing so I realised that the mag box was sitting slightly proud. Thought I’d just not fitted it correctly into the action, so pulled apart and checked again. Mag box sitting correctly in action. Fitted stock and bottom metal and took careful note of mag box.
It was binding on the bottom metal and this got worse as the action screws were torqued down. The mag box should be free to move slightly - right ?
So out with the file and Dremel, hour or so later with frequent fitting checks I got a nice slightly loose fit with mag box and no binding when action torqued up.
Tomorrow’s mission run some rounds and keep me fingers crossed.