most obvious thing is the Serial Number. It will appear on both the
slide and frame. It is XX826 on the left image, 86912 on the right
image. More about Serial Numbers is
next thing you might notice is the US importer, HK in Chantilly, VA.
US importers are required to stamp or engrave their name on any guns they
import. All the "official" HK imports will be by HK in Chantilly.
Some "gray market" imports may show other importers
Date Code is circled in red on the first image, IG. It is IE on the
second image. More on Date Codes below.
M13 or M8 (obviously) mean it is an M13 or an M8. Without an M number,
it is likely a PSP. If the magazine has the release at the bottom,
it is a PSP.
the marks in the second picture are all shiny, bare steel. This is
because they are applied by the proofing house after the gun has been completed
and finished by HK. The serial number was also applied last by HK,
and is also bare steel. If those marks are not shinny as in the first
image, the gun has been refinished (or the owner put a dab of cold bluing
gun in Europe must be sent to an independent Proofing House. They
will fire the gun with a "proofing load" -- a round overloaded with powder.
If the gun doesn't explode, they will stamp their marks on the slide and
frame -- on the barrel itself sometimes, especially if the gun has interchangeable
barrels. The "bird" is a "Federal Eagle" and with the "N" under it
that means the gun was proofed with smokeless power, Nitrocellulose.
The "antler" is the sign of the proof house, in this case one in Ulm.
Experts will tell you HK uses this proofing house exclusively but that
isn't true, you may see other proofing house
The Mystery Mark
P7 pistols were imported into the United States that have had a certain
mark removed from the slide prior to export from Germany:
told BWB means the German "Bundesamt für Wehrtechnik und Beschaffung"
which translates to "Federal Bureau of Military Technical Procurement."
It also could be "Bundeswehr Wehrtechnik und Beschaffung" which transaltes
to "Federal Armed Forces Defense Technology and Procurement", as the Germans
refer to their armed forces as the Bundeswehr.
the date coding system, each letter corresponds to a number. The
letter 'J' is skipped for proofed firearms, but is present on magazines.
P13 above was manufactured in "IG" or "86" or 1986. The P7M8
above was manufactured in "IE" or "84" or "1984."
are supposedly the serial number prefixes for each model.