Typical groups with the S&W Model 22-4.

Perhaps the finest double action revolver ever made for the
.45 Auto Rim is the S&W Model 625-2.

Excellent sixguns chambered in .45 ACP/.45 Auto Rim have been offered over the past nearly 100 years. In addition to producing thousands of US Model 1917s, S&W also offered a very fine civilian model between the two wars. In 1937, S&W manufactured 25,000 Model 1917s for the Brazilian government and many of these were offered for sale in the 1990s. In 1950, the Model 1917 became the .45 Hand Ejector Model 1950 with about 4,000 made until the end of the run in 1966. My 1917 S&W .45 Auto Rim is actually a hybrid, as it is a military issue 1917 with a commercial 1950 barrel.

The year 1950 marks the beginning of the era of S&W modernizing many of their revolvers with a shorter action and upgraded adjustable sights. The 1950 Target Model with a standard 61⁄2" barrel was chambered in both .44 Special and .45 ACP/.45 Auto Rim. Five years later these two revolvers were used as a platform for the heavy bull barreled 1955 Target .45 and the first .44 Magnum. By the 1980s S&W was building many revolvers from stainless steel and also using full heavy under-lugged barrels. The Model of 1988, or Model 625 was first issued in stainless steel, with a 5" barrel and is perhaps the finest .45 Auto Rim sixgun to be had. A rare version is the Model 625-4. It’s a dead ringer for the .44 Magnum Model 629 Mountain Gun, however it’s chambered for the .45 Auto Rim and marked as the Springfield Armory Bicentennial Commemorative.
Ruger’s Blackhawk .45 Colt is available as a Convertible model with an extra .45 ACP cylinder, and the Freedom Arms Model 97 is also offered in the same configuration. These cylinders will not accept .45 Auto Rim rounds, however the auxiliary cylinder I have for a .45 Colt Single Action will. In 2005, thanks to Clint Smith and Handgunner’s influence, S&W began offering what could easily be argued to be the best fighting sixgun ever produced. It’s the Thunder Ranch Special with a 4" barrel, enclosed ejector, fixed sights, and standard weight barrel. It is, of course, chambered for the .45 ACP and Auto Rim.

Except for the rim, the .45 Auto Rim is the same basic brass case as the .45 ACP. For reloading the .45 AR, .45 ACP dies may be used if the seating die is set up to roll crimp. It’s only necessary to add an extra shell holder. Any loading data for the .45 ACP can also be used for the .45 Auto Rim and any 250-260 gr. bullets designed for the .45 Colt also work in the .45 Auto Rim. Since the .45 Auto Rim is shorter than the .45 Colt, .45 Colt loading data cannot be used in reloading the .45 Auto Rim.

For many years the only source of ammunition and brass for the .45 Auto Rim was Remington. The only .45 AR ammunition from Remington I have ever encountered has been loaded with round-nosed lead bullets. I don’t believe Remington offers either .45 AR ammunition or brass any longer, however Starline has excellent .45 AR brass and, with the advent of the S&W Model 22-4 Thunder Ranch Special, Black Hills is now cataloging what is probably the best .45 AR ammunition ever offered. This factory ammunition is loaded with a 255 LSWC and out of my 5" S&W Model 625-2 clocks just over 800 fps and places five shots in 11⁄4" at 20 yards.

From time immemorial both Colt and S&W .45 caliber sixguns have been plagued with the same problem of oversized chamber throats. Looking at two .45 AR sixguns, we find my Model 1917 measures .456", a Model 25-2 measures .455"; and a Model 25-5 in .45 Colt readily accepts a .457" plug gauge. Of course, none of these are normally conducive to good accuracy when shooting .451-452" bullets.

When S&W started using stainless steel for their .45 revolvers they also tightened up their tolerances and three Model 625s I have, two in .45 AR and one in .45 Colt, all have the .451" chamber throats. Apparently this same attention to detail also spilled over into later Model 25s as two I have measure .451" and .452", while their earlier counterparts are as mentioned above.

S&W has carried the use of tighter tolerances over to the Thunder Ranch Special .45 AR as it measures out at .452". Unless one is a reloader who can tailor-size cast bullets, it’s a good idea to measure the throats of any earlier .45 Colt and .45 AR revolvers from S&W or Colt for that matter. Using the Black Hills factory loaded .45 AR round gives a good indication of the importance of tight throats. Two Model 625-2s group this ammunition in 11⁄4" and 11⁄2", while the Model 25-2 with a .455” throats opens up to 21⁄4". However, this latter sixgun defies all logic! Oregon Trail’s .452" 255 SWC over 6.0 gr. of Power Pistol is right at 800 fps while placing five shots in 1" at 20 yards, and NorthWest Custom Projectile’s 260 gr. .452" jacketed bullet over 6.0 gr. of Universal performs the same way. I find this most interesting — and perplexing.

No Magnums here; 250-260 gr. bullets work  just fine.

For most loading chores for the .45 AR I go with the same weight bullets normally used for loading standard .45 Colt rounds, 250 to 260 gr. cast bullets. In modern revolvers such as S&W Models 25, 625, and 22-4, loads can safely be assembled in the 900 to 1,000 fps range. In my 1917 Smith and a 2nd Model Hand Ejector .455, which has been changed to .45 AR, I do not go over 800 fps with these loads, which is exactly the level of Black Hills .45 Auto Rim ammunition with a 255SWC.

Two favorite old Lyman bullet molds for the .45 Colt, Elmer Keith’s #454424 and Ray Thompson’s gas checked #452490, are pressed into service for heavy loads in the .45 Auto Rim. With my alloy, both of these cast out around 255-260 grains. Thom.’s bullet was actually originally designed for use in the .45 AR in a Model 1950 Target. With 7.0 gr. of Unique both bullets clock out at about 925 fps and group right at 1" in the 5" Model 625.

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