Ed: there were calls for a U.S. Government Proof House in the April 20, 1895 Sporting Life
https://digital.la84.org/digital/collection/p17103coll17/id/48142

And in July 27, 1895 a call for a Government Proof House for Nitro Powder Testing
https://digital.la84.org/digital/collection/p17103coll17/id/48122

I suspect the same apprehension regarding letting the government decide what guns were "good" was present then, as now. And the U.S. makers were proving their guns in-house

[Linked Image from photos.smugmug.com]

And proof testing is available at:
Entropy Engineering Corporation
http://www.entropyec.com/

Chesapeake Testing
https://nts.com/services/testing/

Dayton T. Brown
https://www.dtb.com

I don't know anyone who has elected to prove their barrels, and don't know the cost thereof. Should proof testing be required by government edict, the cost would of course be passed on to the consumer.

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