Printer Friendly

Separated at birth? the surprising similarities between the .38 WCF and .40 S&W.

Why would I combine a rimmed, bottlenecked cartridge introduced by Winchester in 1879 for their Model 1873 rifles with a rimless, straight cartridge introduced by Smith & Wesson in 1990 for autoloading pistols? Especially, since one is "38" and the other is "40."

It's because they use the exact same bullet diameters and with some reservations both rounds can be loaded with the exact same bullets. I do it all the time. Furthermore, they shoot those identical bullets to identical velocities from similar barrel lengths.

For some reason--one causing enormous confusion ever since-Winchester Repeating Arms squeezed down its wildly popular .44 WCF to take bullets of 0.400-inch but named the cartridge .38 WCF. Because it could be loaded with 40 grains of black powder other companies wanting to use it in their rifles started stamping them .38-40. Marlin was one such company.

Then in 1884 Colt Patent Firearms got into the act and added it as a chambering in their Single Action Army revolver (aka Peacemaker) and their double-action Model 1878DA. Interestingly, in those days of the first generation of production Colt stamped their SAA revolvers .38 WCF. Those SAA .38 WCFs became so popular it was the third best-selling caliber when production ceased in 1941.

If 35 to 40 grains of black powder is crammed into modern .38 WCF brass under a 175/180-grain bullet and fired down a 4-3/4-inch barrel the muzzle velocity may break 900 fps. (Depending on exact brand and granulation of powder) If a max load is chosen from a reloading manual for .40 S&W and fired in a semi-auto with 4- to 5-inch barrel its bullets may break 900 fps also. In simple terms, the old black powder .38 WCF and the modern semi-auto .40 S&W are ballistic twins.

Now let me expand on the idea of using the same bullets in both cartridges. When the .38 WCF is loaded either by a factory or by home reloaders, the bullet must be crimped into the case mouth. This serves to keep bullets secure lest they move forward in their cases due to revolver recoil or, in repeating rifles with tubular magazines, they could be pushed into the case by recoil and magazine spring pressure. Consequently all .38 WCF bullets--whether lead alloy or jacketed--must have a crimping groove (lead alloy ones) or knurled cannelure (jacketed ones).

Conversely, .40 S&W bullets need no such cannelure or crimping groove. Handloaders will secure them in cases by means of a taper crimp or sometimes just rely on friction to keep them in place.

So here is the situation in a nutshell. Any .38 WCF bullet is fine to use in .40 S&W reloads but the reverse is not true for the above reason--no crimping groove or cannelure.

Therefore, upon buying my first .40 S&W pistol, a Kimber Pro Compact about a dozen years ago, I had no reason to also buy specific bullets for handloading because I had been casting bullets for .38 WCF's since 1983. All of those .38 WCF designs were roundnose/flatpoints (RN/FP), which give perfect functioning in semi-auto pistols. Recommended sizing diameters for lead alloy bullets for both .38 WCF and .40 S&W are 0.401-inch. Jacketed bullets intended for both rounds are 0.400-inch.

This interchangeability of cast bullet designs leads to one conundrum. None of the big bullet mold manufacturers mention it. Each label .38 WCF and .40 S&W cast bullet designs separately. Here's another bit of a puzzle. Most cast bullet designs specifically meant for autoloading pistols from .32 ACP to .45 ACP are roundnose. None of the .40 S&W designs offered by RCBS, Redding/SAECO or Lyman are roundnose. All are semiwadcutters. That's not a bad thing. I just find it odd. I have a few of those .40 S&W cast bullet designs and find that they shoot no more or less accurately than .38 WCF bullets in my Kimber.

After plenty of shooting both handheld and from machine rest I've settled on two lead alloy bullets for almost all of my .38 WCF and .40 S&W hand-loading. When time constraints won't allow me to pour my own, I use Oregon Trails' .38 WCF bullets. They are cast of a very hard alloy and come sized 0.401-inch. When casting my own, the trail splits just a bit. For .38 WCF revolvers the alloy used is 1:20 tin to lead. For .40 S&W I switch to Linotype as that's what I use for all autoloading cast pistol bullets, even keeping one lead furnace dedicated to it.

Both .38 WCF and .40 S&W can share one other component: powder. My handloading with both cartridges has used most smokeless propellants in burning rate from Bullseye to Unique. All are good but if forced to choose one powder for both rounds I'd pick Winchester 231.1 don't have to use one powder and so IMR's Trail Boss is used more for .38 WCF nowadays due to its ability to take up so much case capacity.

It is interesting that after considerable testing by firearms and ammunition manufacturers along with law enforcement input, the cartridge they came up with for modern pistols exactly duplicated one lawmen in the black-powder era thought well of.

COPYRIGHT 2015 Publishers' Development Corporation
No portion of this article can be reproduced without the express written permission from the copyright holder.
Copyright 2015 Gale, Cengage Learning. All rights reserved.

Article Details
Printer friendly Cite/link Email Feedback
Title Annotation:MONTANA MUSINGS
Author:Ventorino, Mike
Publication:Guns Magazine
Geographic Code:4EUUK
Date:Nov 1, 2015
Previous Article:The wisdom of Jeff Cooper: by and large, his teachings have stood the test of time 50 years later.
Next Article:New rimfire clones: these understudies of famous arms are just as accurate and reliable.

Terms of use | Privacy policy | Copyright © 2018 Farlex, Inc. | Feedback | For webmasters