When I lived out on the East Coast, on Fogo Island, I once saw an interesting Tamarack lath.
The man who showed it to me had TIED IT IN A KNOT.
Tamarack, in that part of the world, is called "Juniper" for some reason or other. The Americans call it "Hackmatack". It is very hard, very difficult to work with, very pretty IF you can saw planks from it. It makes lovely boats although it is rarely used for that: too hard to work with. More common is a "Juniper" keel or ribbing.
The Tamarack lath had been STEAMED for a day in a piece of Culvert-pipe which had been sealed at the far end, the near end being balanced atop a steel barrel in which the fire for the shop was burning. The wood to be bent was a foot or so away from the fire-barrel and extended along inside the Culvert. Water tossed into the corrugated near end of the Culvert was heated by the fire below and turned to steam which entered the wood, permitting it to be bent. This is pretty much standard procedure for bending ribs for small fishing-boats.
So the lath was steamed and removed from the steamer, tied into a knot and nailed to the wall of the shop. It was taken down the following day, after it had had time to cool and dry.
So the sequence here was
Steam
Flex and Clamp
Cool and Dry
I would follow this with a quantity of boiled oil to stabilise the wood.
If you don't want to try that, there is always Cork sheeting laminated in with BLO.
Me? I know it's barbaric, but I repair my bedding with Acra-Glas Gel. I think the old-timers would have used it if they had had it. But they did not, so they did the best they could with what they had. Nice thing about Aca-Glas is that you can remove it later if you want to: treat it with ACETONE and it turns to powder, just as any other fibreglass resin.
Hope this helps one way or another.
That is one BEAUTIFUL rifle.
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