Hi Anna,
This is a fascinating question, and not one I've encountered before. I don't have expertise in firearms, so I hesitate to speculate beyond the general collections concerns that come to mind (such as residue, muzzle blast, and combustion byproducts).
I reached out to someone on the Connecting to Collections Care expert list whose specialty includes firearms to see if they have any experience with this specific scenario or know of any relevant guidance. If I hear back, I'll share in another reply.
In the meantime, I'm interested to see if others have encountered a similar situation and can speak from firsthand experience.
Best,
Kate
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Kate Jacus
Connecting to Collections Care Monitor
Preservation Education Specialist
Documentary Heritage & Preservation Services for NY (DHPSNY)
*based at the Conservation Center for Art & Historic Artifacts
Philadelphia, PA
USA
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