WHAT DOES H.P. MEAN? REALLY?

[Don M]

I have an alternate theory that may explain the ground-off stock lugs on these Lugers.

The organization represented by H.P. was apparently very meticulous, almost paranoid, about marking its property. Every major piece of a Luger rig was stamped with a property mark: frame, receiver, both mags and holster. Perhaps removal of the stock lug was yet another means of identification.