Serial Number Placement:
All M1911s have only
one serial number location and it is on the receiver. In 1937, following a
long period with no pistol procurements, the military pistol production
restarted (at serial #710001) and Colts began applying the serial number
to the slide as well as the receiver.
This numbering of the slide and receiver was their normal
commercial practice at the time.
Colts continued the double numbering until about serial #1140000 when it
was discontinued as unnecessary.
On all M1911A1s (1924 to 1945) produced by all
manufacturers the serial number is located on the receiver
between the stock and slide stop hole on the right hand side.
Colt Serial
Number Styles:
First Roman to about Serial Number 4500, then
Arial/Block to end of M1911 production. When production started again in
1924 It then went Roman again at 700001 to 1945 at about Serial Number
2270000 when it went back to Arial/Block
S/N is forward of the
slide stop hole
 |
S/N is between the
stock
and slide stop hole.
 |

|
Serial number location from
S/N 0 to 7500 |
Serial number location from
S/N 7501 to end of production |
Serial number location under
firing pin retainer plate
(S/N 710,001 to about 1,140,000). |
Note: Due
to military maintenance practices as well as barracks cleaning mix-ups,
1911A1 numbered slides were often mixed up and a number of 1911A1s in this
serial number range will be found with numbers that are off by only a few
numbers. Many others will
simply have mixed up slides and receivers. A
non-matching slide will reduce the value of a pistol to a collector
considerably. Yet pistols
just beyond where the slides were numbered may bring considerably more
money than a numbered pistol when the slide just a few numbers off. Yet
there is no way to tell if the un-numbered slide matches either. Commercial
Note:
In part of the year 1920 some Commercial Government Model pistols had
a serial number on the slide underside in front of the
disconnector well as well as on the receiver. This practice only lasted a
few months and the slide serial number was moved to underneath the firing
pin stop plate. Some military
pistols brought back by returning WWI vets were apparently sent to Colts
for refinishing in that small time slot, and while refinishing, Colts
applied their military serial number underneath the slide as was their
standard practice for those months. Reference Charles Clawsons “Colt
.45 Service pistols”.
|