Guns, Firearms, Projectile Weapon Sports/357 Mag to 9MM


QUESTION: I have a J.P. Sauer and Sohn "Chief Marshal" .357 Magnum. I read a few years back that if I changed the cylinder to a 9MM I could fire 9MM ammo (which I have a lot of) with no problems. I can no longer find the article and wonder if you have heard of such a modification? Any help greatly appreciated.

ANSWER: Les, thank you for your question. Let me begin by saying your revolver was manufactured by J.P. Sauer in Eckernforde, Germany and was imported into the United States by the Hawes Firearms Company in Van Nuys, California. The guns were manufactured and imported during the 50's and 60's in response to the cowboy craze in the U.S. brought about by radio and TV programs of the time.

Back to your original question.... The quick answer is yes, what you want to do can be done. Ruger actually has a Blackhawk Convertible Model that comes with a .357/.38 cylinder and a second cylinder in 9MM. The rest of the answer is a bit more complicated. A straight wall handgun cartridge (such as the .357) has a rim around the base that keeps the cartridge from sliding all the way through the cylinder. A semi auto pistol cartridge has no rim, relying instead on the cartridge headspacing on the actual case mouth of the brass.

Because of this a separate cylinder would have to be manufactured from scratch. I have never seen or heard of a 9MM cylinder made for your revolver. That does not mean such a cylinder does not exist.... it might be worth your time to do a bit more searching. As far as having a cylinder made... there are companies that can do that for you but the final cost would probably be more than simply buying an existing .357/9MM convertible such as the Ruger.

Thank You for submitting your question and I wish you luck in your search.

Don Orem

---------- FOLLOW-UP ----------

QUESTION: Don, thank you so much for your quick and knowledgable answer. I appreciate your expertize and time. F.Y.I. after much searching I found a company (Numrich Gun Parts Corp) that listed used 9mm cylinders for my gun in stainless and blue.....But unfortunately they both were sold, I guess I'm not the only one looking. Thanks again for your help. Les

Les, one word of caution... your gun (and any factory cylinder you find) is approx. 50 years old. In that amount of time there is no telling how much wear has taken place. If and when you find a 9MM cylinder I would strongly recommend having an experienced gun smith look the gun/cylinder combination over to determine compatibility. If the gun or new cylinder has seen a lot of wear it could effect the lockup and/or timing resulting in the gun "shaving lead" (a condition where the chamber in the cylinder does not line up with the barrel that causes lead and gas to escape to the side)  or other conditions leading to injury of yourself or those around you.

Good luck in your search and shoot safe!


Guns, Firearms, Projectile Weapon Sports

All Answers

Answers by Expert:

Ask Experts


Don Orem


There are always questions pertaining to any subject that even an expert can not answer. That being said, I am very well equipped to answer questions concerning rimfire firearms due to experience, research, and discussion of rimfire firearms with many people I consider experts. I collect old, different, or unique examples of Rimfire firearms. I also have an extensive collection of handguns and rifles from all over the world. I reload, shoot black powder, and have a nice collection of military firearms dating back to the 1800's.


I started shooting in 1953 when I was 5 years old. My father bought two .22 single shot rifles, mine was a Springfield Model 15 that I still own to this day. Today it would not be tolerated or politically correct, but back then he taught me gun safety and how to shoot by taking me to the town dump where we shot rats. Maybe that is to much information but those are some of my best memories of spending time with my father. I am at my gun club range at least 2 or 3 days a week. I am a certified NRA instructor and I teach both Basic Pistol as well as Home Firearms Safety. I also teach Concealed Carry Classes here in Florida. I have been a squirrel hunter all my life and for the last 4 years I have been active hunting feral hogs in the Everglades. I have been to every Shot Show for the last three years on my media credentials and I have attended the NRA National Convention for the last 2 years. I have my own on-line gun forum called Gun Tips and Talk and I have also served for a number of years as a Moderator or Administrator on the National Gun Forum and the Florida Gun Forum. I do a lot of gun and equipment reviews on-line. I also have my CCR FFL, a personal UPIN number with the Justice Department, and I enjoy shooting my suppressed .22's. As a side hobby I build competition bench rifles for others on the 10/22 platform. There are a number of reports on my "project" guns on my personal website at .

NRA, NSSF, and the Dade City Rod and Gun Club in Dade City, Florida.

I am a high school graduate with an additional 2 years of college with a major in Commercial Marketing. I am also a disabled Viet Nam Vet.

©2016 All rights reserved.