In the FWIW department, where I have wanted to add weight to a firearm using lead in the stock, I have first poured it into a length of copper tubing, making a very dense cylinder of whatever length provided the necessary weight. The cylinder was then fitted in a slightly oversided hole in the stock with a little bit of tape at each end so that it didn't rattle side to side, bt could still allow for stock shrinkage and expansion due to humidity. Then a little dense foam at the bottom of the hole or under the buttplate keeps it from rattling fore and aft. It is best if the foam is at the buttplate end of the hole with regards to damping the recoil.

In any event, the use of the copper tube seems to inhibit, if not flat-out prevent the swelling of the lead due to repeated impacts of recoil and/or oxidation.

YMMV

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BrentD, (Professor - just for Stan)

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