Wish I had a better place to post this ... I'm using the old barrel but this pic is about how narrow a plank you can get and build a gun with it . This is all about being s cheap $hit like me , LOL , so bare with me . I font suggest you do this if you can afford a good piece of wood for yur stock . 2" thick for a fowler and 2 1/2" thick for a rifle minimum. But ....poor folks got poor ways so ...here ya go . Ive tried to explain this to folks but have always fallen short in my explanation. I got the barrel exactly in the center of the plank and I'm holding a lock plate with bolster up again it ...look at that tail . Its in there , just barely but its in there not hanging over with a hap between the tail and wood so ....with this plank I'd be good to go for a build ....just barely . and , the neat thing , is is under 1 3/4" thick ! Crazy .... Narrower the board usually easier to find locally . A specialty shop you can find 2" and thicker boards or planks but locally hard to find them . Some times , like a build I had a few builds ago , a was using a barrel that had a lot of flare at the breech , the RE Davis lock end stuck out away from the wood so I though I couldnt use that board BUT I switched and check with an L&R Queen Anne lock and it was just fine soni built the gun with the Quern Anne . Turned out great . Just a trick of the trade from a cheap skate hillbilly.