Cast Bullets for the .32-40
Date: Oct 25 2013
While the .32-40 cartridge was actually a mid-1880s Ballard blackpowder development, it is often referred to as the .32-40 Winchester. The Winchester firm eventually posted its name behind the cartridge designation and chambered it in both the 1894 lever action and 1885 single shot.
Even considering its heritage as a target round, original .32-40 ballistics seem a bit feeble in comparison with today’s cartridges. A 165-grain lead bullet at just under 1,400 fps when fired in a rifle is not much different than a .357 Magnum round fired from a revolver.
When I found a dealer with several reintroduced Winchester 1885 Traditional Hunters in .32-40 for sale, the opportunity to work with the cartridge could not be overlooked. The Traditional Hunter is basically a “high-wall” single shot with a tang sight, 28-inch octagonal barrel, straight-grip stock and a steel crescent buttplate. The barrel is drilled and tapped for scope use. Weight is around 9 pounds. What I was unaware of at the time of purchase was that the rifles were in far greater supply than the ammunition (and unprimed brass) for which they were chambered.
Winchester makes the brass and ammunition but not on a regular basis, as the demand for anything .32-40 is less than overwhelming. Back orders from two suppliers went unfilled for a year or more, but I finally located 200 new, unprimed cases. Before receiving the brass, however, I re-formed 60 Winchester .30-30 WCF cases by running them through a .32-40 sizing die. This was easily done using two steps. A lubricated case was forced about halfway into the die and removed. Additional sizing lube was applied, and the case was forced into the die once more for complete forming. Such cases are shorter than .32-40 brass by .091 inch. The only disadvantage in using .30-30 cases is that with some cast bullets, one or more lube grooves are left exposed when bullets are seated. I’ve since learned that many handloaders use re-formed .30-30 WCF brass in .32-40 rifles; .38-55 brass is longer than .30-30 but still a little short, so some might prefer that route. While I have not used any, Starline makes a .38-55 “long” case that reportedly takes care of the length problem when forming the .32-40.
Several hundred rounds were chronographed using both reformed .30-30 WCF and Winchester .32-40 brass. Save one exception, velocity figures indicated that if there is a difference in case capacity with a seated bullet, it is of no consequence. There were some discrepancies in seating depth between the two cases, but that means little to most handloaders, who would tailor bullet seating depth for individual rifles anyway, particularly for use in single-shot rifles. The time-tried rule for cast bullet seating prevails here: Seat a bullet as far out as practical so that a loaded round may be extracted without leaving a bullet stuck in the rifling origin. Some of the overall lengths listed in Table II are far too long for lever action rifles and would require deeper seated bullets. Since a single shot rifle was used for load development, no case crimp was used. Crimping would be a must for use in the magazines of lever-action rifles.
Internal barrel dimensions of the newly produced Winchester 1885s are in compliance with .32-40 SAAMI specifications. Twist rate is one in 16 inches, and the bore has a nominal groove diameter of .320 inch. Research indicates this .320- inch figure may have deviated somewhat over the last 125 years. Most .32-40 cast bullet shooters load bullets that measure somewhere in the vicinity of .321 to .323 inch.
Many bullets that measured between .320 and .323 inch were shot with identical powder charges using both the short, re-formed .30-30 brass and the regular .32-40 brass. After a total approaching 1,000 rounds, quite surprisingly, there was very little difference in accuracy. Even with the .323-inch bullets having the overall edge, the variance was slight enough that their use was discontinued.
When developing cast bullet loads, many handloaders begin with the largest diameter bullet (within reason) that will chamber. I’m an advocate of this practice simply because it is usually the best choice from an accuracy perspective. In this project, .32-40 rounds loaded with .323-inch bullets chambered very snugly in the Winchester’s chamber, perhaps too snugly from a safety standpoint. Loads using .321-inch bullets chambered much more easily, though not loosely like a factory round.
Bullets were cast of wheelweight alloy with an average Brinell hardness number (BHN) of 13. Leading was a minor problem with some of the faster loads, and bullet diameter had no apparent effect on it. I tried two lubricants. NRA-type half-and-half was used initially. Despite being messy to work with, its performance is fine in most instances until velocities exceed about 1,800 fps. Farther along in the task, I experimented with a lubricant that I was unfamiliar with, Voodoo Red. This lube is firmer and easier to work with than half-and-half but is softer than “hard” lubes.
In terms of accuracy and the reduction of bore leading, there was no discernible difference between Voodoo and half-and-half. That’s praise for Voodoo, not criticism. The two can be used interchangeably. Voodoo might outperform a half-and-half lube at higher velocities, but there is little opportunity for high velocity with the .32-40 cartridge. For anyone interested in trying Voodoo Red – follow directions! The maker mentions “seasoning the bore,” a phrase that makes many think of snake oil treatment. The procedure is simple and the recommendations are to shoot with a fouled bore, never cleaning completely as most shooters do. I tried it both ways, as suggested by the manufacturer and with a completely clean bore. With a perfectly clean bore, the 1885 produced noticeably larger groups.