[Scott Gahimer]

In March 1913, proof ammunition was first received at Colt and began being used to proof test barrels. Mr. Clawson states the first barrel tested was for pistol s/n 24251. This pistol, s/n 24279, is one of the very first pistols to have a proof tested barrel.

These first proof tested barrels are marked in a unique fashion. The H is on top of the chamber and the new "P" proof mark is applied to the back side of the barrel hood extension. By about s/n 25000, the "P' was moved to the top of the chamber, thus introducing the horizontal P H barrel.

This pistol was carried, but appears to have not been used too much.

 

[Oyeboten]

Interesting!

Details within details with these...

 

[Malysh]

Very informative. I have seen a few pictures of barrels stamped with the P proofing on the area that you have mentioned, but not being an expert on M1911 pistols, I didn't know the significance of the stamping in that area.
Thanks for the info and pictures.
Nice example.