LETTER TO THE EDITOR
I have recently purchased a Colt 1921 Thompson that belonged to the Pa. State Police. The serial number is 1193. Since I am a Trooper; I was very interested in finding out as much as I could about PSP Thompsons. I am writing you so that you pass this information onto other owners of PSP guns. The information is in two forms. Facts I could verify through documents and photographs, and best guess/ideas that I could get by speaking with department personnel, both active and retired.
First, the facts. The Pa. State Police had thirty one 1921 Thompsons deployed to the field. All were 1921AC's. All were deployed with vertical foregrips. All had property tags on the wood, (a small white tag with "Pa. State Police" and a five or six digit number.) All had sling swivels on the buttstock and swivels installed on the front of the vertical foregrips. At first twenty rounds stick mags and fifty round drums were used, then thirty round stick mags were added. The department does have other Thompsons but they are used in the Ballistics lab and were not deployed to the field.
Now we come to the best guesses. There is no evidence of shot mags, one hundred round drums nor any web gear such as drum pouches or canvas gun cases being used. The next guess may upset some collectors. It is based on a interview with the PSP gunsmith, the examination of two Thompsons still owned by the department and a check of left over spare parts still in inventory at DHQ. It appears that all PSP Thompsons had 1928 actuators installed in them. I do not know if this was done in the field or at central supply. The gunsmith related that he had never seen a 1921 actuator or a 1921 recoil spring. There are 1928 recoil springs left in inventory. Both of the guns retained by the department have 1928 actuators installed. Where the 1921 parts are now is unknown, and when this change was done is unknown. I've seen only a few pictures that showed slings installed on the guns, and none of the enlisted people I spoke with remember seeing a sling installed on any of the guns. In the few pictures I've seen that show slings, it's hard to make out what kind of sling is used. However, in one picture the sling appears to be a Kerr sling.
The history of the guns is at best thin. when they were purchased is unknown. Some if not all may have come from the Pa. Bureau of Mines. They were removed from service in 1983. They were sold in 1983 and 1988. Several were used in shootouts, but which particular gun was used is unknown.
That's all I could find out and if anyone has other or different information let me know. I've included pictures that show the gun, sling, property tag and correct shoulder patch for when the guns were last used.