The Model 1917 Had The Back Of The M1911
When the US gunned up for World War I, it pressed a lot of manufacturers into service to make the M1911 pistol. All of that manufacturing wasn’t enough, so it turned to Colt and Smith & Wesson to modify their large frame double-action revolvers to take the rimless .45 ACP cartridge and the Model 1917 was born.
Ordinarily, revolvers take rimmed cartridges. It’s cheaper, faster and easier to bore cylinder chambers straight through, but a straight-walled, rimless cartridge can drop into the chamber so far that the firing pin doesn’t hit the primer. To solve that problem, S&W came up with the half-moon clip that, as the name implies, is a half-moon shaped metal clip that holds the .45 ACP rounds by the extractor groove, basically headspacing the rim against the clip instead of the mouth of the case against the chamber shoulder.
The most notable difference between the Colt and S&W is that generally Colts are found with chambers bored straight through while S&W actually used a chamber reamer so there is a little shoulder in the chambers and you can fire .45 ACP cartridges without the clips. The trade-off is that you can’t eject fired cases using the extractor star and you have to push individual cases out from the front of the cylinder using a pencil or other type of punch. Later, Peters came out with the .45 Auto Rim, which is a rimmed version of the .45 ACP that you can shoot in any 1917 revolver without half-moon clips.
One variant of the 1917 is the Brazilian contract known as the S&W 1937. There were 25,000 of these guns made for Brazil and they’re easily identified by the Brazilian crest. I have both a S&W 1917 and a 1937, but I had Stanton Wormley of Leckie Professional modify my 1937 for carry. Stanton bobbed the hammer, turned in and shortened the grip, chopped the barrel off in front of the ejector shroud and gave it a “creek bed” finish to hide some of the small rust pits. I fashioned new grips out of oak and wrapped them with a rubber slip-on grip because this little gun stings a bit when you shoot it.
Today the are half-moon clips, moon clips, two-cartridge clips and with a Dremel tool you can even fashion E-clips into single clips to shoot rimless cartridges in revolvers. Popular rimless cartridges that use moon clips in revolvers include 10mm, 9mm and .40 S&W.
Stanton did a great job on my 1937, but in hindsight I wish I hadn’t assed up this gun and left it original. A large-frame S&W is just too thick for me to carry concealed. If you do find an original 1917 or 1937, keep it original.
“Shooting Guns & Having Fun”