Ok now for the long answer. Victory models fall into several categories.
#1) Pre-Victory, these were in Brit. 30-200 cal (38 S&W) these were sent to Briton by S&W as recompense for a failed Semi-Auto carbine contract.
Most were Blued w/checkered stocks and had 5 inch barrels. These may not have a "V" prefix to the serial number.
#2) Lend-lease Victory models, these were also Brit. 30-200 cal (38 S&W) but were Parkerized or Magic Black finished. These will be U.S Property marked. Some, but not all will have British Commonwealth military unit marks or proof marks (some did go to South Africa in 38 special). Again these were 5 inch barrels. These will have a "V" or "SV" prefix to the serial number.
#3) U.S. Service Victory models were Also U.S. Property Marked and were 38 Special. Some were Unit or Branch Marked (U.S Navy). Most were 4 inch but few were 2 inch barrels. These will have a "V" or "SV" prefix to the serial number.
#4) Defense Plant Victory models, these were used for civilian guards in the U.S. these mostly were unmarked, but can have rack numbers or company names on them. they can be 38 special or 38 S&W with 5 inch or 4 inch barrels. These will have a "V" or "SV" prefix to the serial number.
#5) Postwar Victories are leftover frames used to make commercial revolvers after the war. These will have a "SV" prefix to the serial number.
Finally, the "C" prefix started in 1948 after the last Victory frames were used up.
Please note that there are exceptions to the above, thats why it's fun to collect the Victory.
popgun
I will add that Popgun is almost correct except that he twice typed .30 where he means .38/200 (.38 S&W.)
And prior to April, 1942, guns going to the Commonwealth might have four, five, or six-inch barrels. I've seen all, and many of the ones for South Africa did have four-inch barrels. Digi-Shots on this board has one, and I think another member may have. They will often have a "U" with the Broad Arrow property mark within stamped on them. The U was for Union of South Africa. After about 1960, this became Republic of South Africa, but that is beyond the time frame of our story.
After April, 1942, the Commonwealth guns were made only with five-inch barrels, and the grips were smooth walnut. Prior to then, the British and other Commonwealth guns were essentially just M&P's chambered for the .38/200 cartridge, with lanyard rings standard. They had blued finishes and checkered grips, with silver S&W medllions at the top of the grip panels.
All true S&W US Victory Models for official use were in .38 Special, save that some .38/200 guns were furnished to the OSS, for reasons never made clear. They had dull black/gray finishes, and tool marks were often not polished out properly, to speed wartime production. These were standard issue to Navy and Marine pilots and many other Naval personnel had them. (JFK had one aboard PT-109.)
Plant guards may have had some that were overruns at times from British contracts, but most of theirs were also in .38 Special.
By the early 1960's, many of these Victory Models, some commercial M&P's and some equivalent Colts (Commando and Official Police) were transferred to the USAF, until that agency had acquired enough Combat Masterpiece .38's to meet all their needs. I don't know what became of these after that time.
It is important to note that during and after WW II, standard commercial guns were serving alongside Commando Colt and Victory Model S&W's. Colt also supplied their .38 guns to Britain, but not in as large numbers as S&W did. Well over 568,000 Commonwealth S&W's were shipped, and they are among the more common military handguns of all wars.
Keep in mind, too, that Colt was furnishing their .45 automatic to the British, for Commando and clandestine troops, like SOE. The Colt .45 was the standard Commando handgun for Army units. (Royal Marine commandos may have used other models. Ian Fleming saw many .455 Webleys among them.)
This is a good summary, and for further reference, it may be best to acquire the basic S&W books and read any books by men whose wartime service involved using handguns. One interesting one is, "We Die Alone", by David Howarth, a Norwegian resistance fighter. (Colt .32 auto.) Another is, "The Hundred Days of Lt. MacHorton" (Colt .38/200).
Alas, many soldiers, sailors, airmen didn't specifically mention make or model numbers of their pistols. Col. David Niven just mentioned his "Webley." And one SAS man called his .38 a "Smith & Weston". Obviously, his memory was flawed, or he didn't read the name on the barrel too carefully! (Or, author Virgina Cowles, who recorded his oral recollections, misspelled it in, "Stirling's Desert Raiders".)
If your gun was SAP issue, it may well be a postwar commercial gun, Model 11. The only difference from Model 10 was that Model 11 was in .38/200 caliber. This being after the wartime emergency, those guns had the commercial blue finish. BUT... be aware that the US Post Office bought some .22 M&P's and THEY were also designated as Model 11! I trust that this is sufficiently confusing?
Perusal of wartime photos will also reveal many handguns.
Note that US Navy and Marine aviators prior to mid or later 1942 usually had Colt .45 autos, the .38's just beginning to reach them in quantity after the Battle of Midway. You can tell this in pictures in, for instance, "National Geographic."
I hope this was of help.
Oh: Charlie S. has a point. In fact, .38 Special M&P/Model 10's with five-inch barrels and lanyard loops were the standard sidearm of the RCMP from 1954- until some time in the 1990's.
T-Star
