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From Ingot to Target: A Cast Bullet Guide for Handgunners©
Cast bullet lubrication
In the days of the matchlock and flintlock, the cast lead balls used for all military and hunting operations had no need for lubrication. The cloth patch served as a physical buffer to prevent galling and abrasion, thereby limiting metal fouling. In addition, it (in conjunction with the ejected solids inherent to black powder) helped to seal the gases behind the projectile, limiting gas cutting. Everything was fine until it was discovered that bullets flew straighter if spun in a tight spiral. Although numerous methods for imparting this spin were tried out, it was found that the best method was to cut rifling grooves into the barrel, which in turn cut into the bullet’s surface and forced it to spin, resulted in significantly more predictable flight (i.e. better accuracy). Prior to this the ballistic inefficiency of the round-ball projectile was not considered a problem because accuracy of the smooth-bore was more of a limitation than was the arching trajectory of the ball.
However, once rifling was introduced into the mainstream, the limitations of the round-ball projectile quickly became apparent. In order to take advantage of the new accuracy capability, longer, heavier and more ballistically efficient projectiles were necessary. It was also necessary to engrave the metal bearing surface of the projectile in order to impart the desired spin, a cloth patch was no longer adequate (although greased wads were occasionally loaded beneath the elongated bullets). Several problems were immediately encountered. First, it was very hard to engrave these bullets during the muzzle-loading process. Something was needed to ease and speed this process. Second, the newfound accuracy quickly degraded after only a few shots. In an ideal world this wouldn’t be a significant limitation in the hunting fields since (hopefully) the first shot would drop yon buck and feed the family, but in a military or defensive situation this was clearly unacceptable (and keep in mind the American frontier during this time, the middle part of the 19th century, was not a gentle place, the family firearms might well be needed on a moment’s notice for defense from outlaws, hostile tribes, or pack of wolves). Thirdly, metal fouling was severe when these longer bullets were loaded and fired “bareback”. What resources did the frontier sharpshooter have on hand to address these problems? Darned few, but one of the commodities that everybody hoarded in those days was tallow. If these longer bullets were cast so that they had a groove around their waists, then a dab of tallow, grease, wax or whatever could be applied to this groove. This material would then lubricate the passage of the bullet down the bore during loading, significantly speeding up the loading process. In addition, it was found that by adding this dollop of grease, the accuracy of the firearms lasted for significantly more shots than earlier, and when cleaning was required to restore the fading accuracy, metal fouling was considerably less (now the problem was primarily black powder fouling). Given this history, it’s easy to see why we call it “bullet lubricant” today – it lubricated the passage of the bullet down the bore and made it easier and faster to load the early muzzle-loading rifles.
Modern sixgunners don’t need to ram a ball down a rifled bore, so is lubricant really still necessary? After all, the projectile starts off lovingly seated into a carefully prepared brass cartridge case, crimped into exact position, over a precisely measured powder charge. Once the primer is struck, the burning powder provides all the horsepower needed to drive the bullet from the case and out the barrel, so why would we need to lubricate it? In fact, how can grease contained in a simple groove in the cast bullet lubricate the bearing surface of the bullet, much of which is in front of the lube groove? Is this gooey stuff really serving a function to the modern sixgunner, or is this just an archaic holdover from days gone by? This chapter aims to address these, and other, issues.
Phil Sharpe, in his landmark treatise “Complete Guide to Handloading” encourages the novice handloader to load 10 unlubricated cast bullet rounds for his favorite revolver, and carefully and deliberately fire them from sandbags at a fixed target and watch accuracy degrade with each shot. Direct experience can be a powerful teacher! Suffice it to say that we still need to lubricate our cast bullets. Without lubrication, the cast bullet will lead a barrel horribly, and in very few shots. You can think of it as being rather like a lathe bit and turning stock – the steel rifling grooves are the hard cutting edge of the lathe bit, and the softer bullet metal is the round stock being turned. The bullet lubricant serves the same sort of role that cutting fluid does in preventing galling of the soft metal onto the harder cutting edge. However, a key difference is that instead of having a steady stream of cutting fluid directed straight onto the cutting tool from a conveniently located nozzle, the bullet is asked to carry its entire supply of cutting fluid with it across the entire bore surface. What’s more, it is asked to efficiently and uniformly deliver that limited pool of cutting fluid to the entire bore surface in a matter of milliseconds. As a result, the flow properties of bullet lube are one of its most important properties (we’ll come back to this in just a little bit). This is a tall order indeed.
OK, so we know that we need to use bullet lube, that lubrication of the cast bullet is necessary to prevent leading and that how it flows under applied force is important to how well it performs in your loads, but how does bullet lube work? And how can we make it work better? How can a groove full of grease lubricate those portions of the bearing surface that are in front of it?
Lube flow properties. Many things can act as lubricants, and virtually anything that can be squirted into a cast bullet’s lube grooves has been evaluated at one time or another as bullet lube. Oils have been found to leak out of the lube grooves of bullets, contaminate the powder charge and severely impact the performance of the propellant. Historically, tallow of various descriptions has been used to lubricate bullets with moderate success. Many different greases have been tested (petroleum based, animal fat based, etc.), but most greases are mobile enough that some sort of stiffening is required to achieve the necessary consistency. Such stiffening is usually accomplished by the addition of some sort of wax, most commonly beeswax which is ideally suited to this application. Also used have been ozocerite, Japan wax, Carnauba, paraffin, and numerous others. Ozocerite (also spelled “ozokerite”) is a non-crystalline naturally occurring hydrocarbon wax, mined from Miocene formations near petroleum deposits. It is slightly higher melting than beeswax, and not as brittle as paraffin. Japan wax is another wax encountered in some of the older bullet lube recipes. Japan wax is obtained from the berries of certain Oriental species of sumac trees. It is not a hard wax, but rather malleable and slightly tacky. Japan wax is a softer wax and has notably lower melting point than beeswax, making it less effective as a stiffening agent than beeswax. It is a fat (a triglyceride) composed largely of palmitin and palmitic glycosides, as well as other fatty acids and diacids. As a result, like any other fat, Japan wax eventually breaks down and becomes rancid, which may explain the accuracy problems commonly encountered with Japan wax based bullet lubes. Carnauba wax is obtained from tropical palm trees, and is an amorphous, hard, lustrous wax (hence its use as car polish). It is composed of hydrocarbons, higher alcohols and their esters. It melts considerably higher than beeswax, and in fact is one of the hardest, and highest melting, natural waxes used commercially, making it a very effective stiffening agent for bullet lube (in fact Winchester used pure carnauba for years as a bullet lube). The fatty alcohols and fatty acids themselves have also been used for bullet lube, but were found to be of limited efficacy. Greases derived from the fatty acids have been found to have excellent lubricating properties for cast bullet shooting (especially the lithium-based greases, like Alox 2138-F), but these greases require stiffening. Various synthetic polymers have also been used in bullet lube formulations. The polyglycols, better known as “Carbowaxes”, have been used effectively in lubes, as have microcystalline polymers like polyethylene and fluoropolymers like teflon.
A detailed discussion of tribology (the study of friction and lubrication) is beyond the scope of this book, but suffice it to say that there are several different mechanisms by which a material can lubricate the passage of one material over another. The wettability of the lube on both steel and lead surfaces is a critical parameter for enhancing lubricity. If the lubricant doesn’t “wick out” and wet these surfaces efficiently (and remember, to lubricate the passage of a cast bullet, it only has a couple of milliseconds in which to do this), it will not do a very effective job of lubricating. However, lots of hydrocarbon greases are very effective at wetting polished metal surfaces, so the wettability issue is pretty well addressed by virtually all bullet lubes (except perhaps the fluoropolymers like Teflon). So, while lubricity is indeed an important property for cast bullets, the flow properties (viscosity, thixotropic properties, etc.) are perhaps the most important. This is because even the slipperiest lubricant won’t do you one whit of good if it doesn’t get to the surface in need of lubrication, and to get where it’s needed it needs to flow. But faster flow isn’t necessarily better since this is a pressurized system and if the lube flows too quickly, then it gets squirted right past where it’s needed, and still can’t do its job. So it really comes down to a balancing act. Nor is it simply a question of viscosity, since the viscosity of the mix can, and does, change as a result of applied shear (thixotropic flow), pressure and heat. So it really becomes a question of the integrated flow properties over a range of conditions that dictate the success or failure of bullet lube. This is a particularly important issue for the hard bullet lubes (we’ll come back to this later).
This is why the stiffening agent chosen can be so important to the performance of a given bullet lube. The lube will perform better if the stiffener has an intermediate plastic phase that allows for viscous flow. Paraffin isn’t nearly as effective as is beeswax as a stiffener for bullet lube – paraffin is a microcrystalline wax that goes directly from a crystalline solid phase to molten liquid phase, there is no viscous plastic phase intermediate. Beeswax on the other hand has an extended plastic range exactly where it does the most good as far as bullet lube is concerned.
Lube pumping mechanisms. Now that we recognize that lube must be able to flow from its reservoir (I.e. lube groove) to wherever it’s needed, the question becomes "What makes it flow from point A to point B?" The fluid dynamics of lube flow has many components: simple displacement, compressive pumping, linear acceleration, radial acceleration, and pressure-induced pumping. When the bullet is engraved, the lands displace not only bullet metal in the driving bands of the cast bullet, but they also displace a certain volume of lube in the lube grooves (assuming the lube grooves are completely filled). This displacement serves to compress the lube somewhat, thereby forcing it into contact with the rest of the bore, as well as into the nooks and crannies of the bullet/bore interface. This is the first and simplest lube pumping mechanism. As the pressure builds, the force applied to the base of bullet may grow to the point that it surpasses the compressive strength of the alloy (particularly for magnum revolver or rifle cast bullet loads). At this point the central core of the bullet in the lube grooves is compressed, getting fatter and shorter, which in turn reduces the volume of the lube groove. Once again this compresses the lube within that groove and forces it to the bullet bore interface. In the early moments of the fired shot, the bullet is being subjected to tremendous acceleration forces. The inertia of the lube in its groove forces it to the rear of the lube groove as the bullet essentially gets accelerated out from underneath it. As the lube encounters the rear face of the lube groove (either beveled or radiused), it is forced outward until it hits the bore surface. This is the linear acceleration mechanism, and it operates primarily in the first few inches of the barrel, and so is of particular interest to handgunners. As the bullet starts to rotate faster and faster as it travels down the bore, the radial acceleration (think “centrifugal force”) increases to the point that it starts to pump lube from the bullet’s lube groove outward to the bullet/bore interface. This mechanism starts to take over later in the trip down the bore, so is more of an issue for longer barreled revolvers, carbines and rifles. The last mechanism for pumping lube from the lube groove to the bore surface, and perhaps the most important mechanism of all, is pressure induced pumping. As the bullet is engraved and travels down the bore, small defects are created on the bearing surface of the bullet, particularly along the trailing edge of the land. While these defects are usually quite small (almost always smaller than .001”), they are nonetheless large enough for high pressure gas molecules to traverse. This channel basically constitutes a microscopic high-pressure gas nozzle. The high pressure, high temperature gas molecules that are driving the bullet down the bore are buzzing like a mad swarm of hornets. When they find this leak, they run up it instantly. What this does is it virtually instantly pressurizes the lube groove and drives the lube forward. There are also microscopic defects in the bearing surface of the forward driving forward of the lube groove, so the pressurized lube gets forced into these crevices and forced to the forward portions of the bearing surface, where it is desperately needed because all of the other lube pumping mechanisms (coupled with the forward motion of the bullet) favor the rearward bearing surfaces of the bullet.
Lube grooves. Elmer Keith designed his semi-wadcutters with what he called “square-cut” lube grooves. These grooves were flat-bottomed with sharply beveled sides (but not actually a full 90 degrees). Some of the older cast bullet designs did indeed have lube grooves cut at 90 degree angles, but these old moulds can be frustrating to cast with as the bullets commonly “hang-up” in the mould and don’t release easily. When bullet metal cools, it contracts, shrinking towards the geometrical center of the bullet. With 90 degree lube grooves, the shrinking bullet metal can “pinch” these grooves and hold fast. Keith avoided this problem by putting a slight bevel on the edges of his lube grooves (on the order of 60 to 70 degrees) so the bullets would release from the mould more readily. Sometime later Lyman modified Keith’s designs by going to a rounded radiused lube groove, which was easier to manufacture and released bullets very smoothly. Keith was highly critical of the radiused lube grooves because the rounded groove didn’t hold as much lube as his original design (he was firm believer in using enough lube). It’s important to recognize that there is nothing wrong with the shape of the radiused lube groove, and it does allow the bullet to release more readily from the mould, but what Keith didn’t like was the size – it just didn’t hold enough grease to satisfy the Old Master.
One can make up for this lack of capacity by using multiple lube grooves, and that is exactly the tact taken in the excellent SSK and LBT bullet designs – several smaller, rounded grease grooves instead of one large flat-bottomed groove. The overall lube capacity is similar, it’s just spread out over a larger area in these more modern designs. When one looks at each of the designer’s goals this only makes sense; Keith was generally interested in making his bullets the “standard” weight for the caliber (e.g. 250 grains for .44 and .45) as a general purpose all-round bullet, and thus didn’t have room for multiple lube grooves, while J. D. Jones and Veral Smith (of SSK and LBT respectively) were primarily interested in making bullets that were heavy for their caliber, for deep penetration while big game hunting. These designs, by their very nature, have significantly more bearing surface and thus benefit from having their lube supply somewhat more spread out.
Note that the angled rear faces of both the beveled flat-bottomed lube groove and a radiused lube groove are equally well-suited to pump lube to the bullet/bore interface by the linear acceleration mechanism (the only form that is handicapped in this regard is the old BP lube groove with the 90 degree edge).
One place where the two groove designs may well differ in performance would be in the compressive lube pumping mechanism. The radiused grease groove may well distribute the compressive stress more effectively and thus resist compression somewhat, limiting how effectively lube might be pumped by this one mechanism. The flat-bottomed grease grooves have stress risors at the vertices which may very well serve as inherent “crumple zones” whose buckling would subsequently benefit this mode of pumping lube to the bullet/bore interface.
The other lube pumping mechanisms should work equally well for all of these lube groove designs.
Sealing the bore. The microscopic defects discussed earlier are also the source of leading as a result of gas-cutting. Bullet lube plays a very important role in preventing this source of leading by acting as a sort of “stop-leak”. The most important bore sealing mechanism is obturation of the bullet metal itself, but the bullet lube can play a strong supporting role if the lube is of the proper consistency. When the hot gases driving the bullet start to leak through the channels left by engraving, they pick up lube and force it into the crevices as they both move forward. By filling these channels with lube, the flow of gases is effectively stemmed, thereby limiting gas-cutting. If these defects are sufficiently large (i.e. rough bore, undersized bullet, irregular lands/grooves, etc.) then the lube simply gets blown forward and out the bore, leaving the bullet naked and severe leading is the observed result. Once again, we see that the flow properties of lube are critical – if it’s too thin (i.e. liquid) and has a low viscosity, then this sealing mechanism is lost and the lube isn’t able to do its job because it’s an aerosol out in front of the bullet. Thus, the “stiffness” of bullet lube is a compromise between being fluid enough to be effectively pumped from the reservoir (i.e. lube groove) to the bullet/bore interface, and being thick enough to form an effective seal once in place. The old adage “Moderation in all things” once again holds true – viscous flow, with moderate thickness is a key virtue for a quality bullet lube. There is no such thing as a perfect bullet/bore seal, there will always be channels and defects that are not sealed. It’s a question of whether or not obturation and lube can team up and make an effective seal.
Hard lubes vs. soft lubes. A veritable plethora of bullet lubes are commercially available today, both hard and soft, and the hard lubes can be had with a variety of melting temperatures (usually by varying the molecular weight of the polymer used to stiffen the formulation). Most commercial hard-cast bullets come with some gaily-colored hard lube, sometimes with a well-defined pedigree, other times from a somewhat more mysterious origin. Is this because hard lubes are better than more traditional soft lubes? No, it’s because hard lubes handle the rigors of shipping better and are amenable to simple bulk packaging, whereas bullets lubed with soft lube need to be packaged a little more tenderly to keep the lube in the groove and not smeared all over the packing materials. The extra packaging and handling makes them more expensive.
But do hard lubes offer any substantive performance advantages over soft lubes? Aside from being a little less messy, no, not really. It all comes back to the flow properties of the lube. Obviously, a solid doesn’t flow very well, at least not in the few milliseconds the bullet is traveling down the bore, so many of the lube pumping mechanism outlined above really can’t do much with a solid hard lube. The modest lubrication needs of low-pressure cast bullet loads are generally satisfied by the hard lube being displaced by the lands during engraving, but the other mechanisms are pretty much shut down. The key here is that for a hard lube to be pumped, it must melt first. The key word in that sentence is “melt”, as in “undergo a phase transition from the solid phase to a liquid phase”. The current formulations of hard lubes use stiffeners that melt (and they are advertised according to their melting temperatures) instead of going to a plastic flow phase (which is how the soft lubes work). Once a hard lube melts, it can be pumped to the bullet/bore interface very efficiently, but it requires that the bullet metal do virtually all of the bore sealing since the low viscosity liquid lube will get blasted out past the bullet if there are any channels left unsealed by bullet obturation. So for effective use of a hard lube, the shooter needs to pay closer attention to alloy hardness than he does when using a soft lube.
For magnum revolver loads, hard lubes tend to work pretty well because the higher pressure of the load is generally sufficient to induce obturation of all but the most extreme of alloys, the higher operating temperatures (as a result of both the larger powder charges and the frictional forces from the higher velocities) can melt some of the hard lube to ensure adequate delivery of lube by the various pumping mechanisms, and the higher pressures can inject small amounts of lube to the forward portions of the bullet and effectively lubricate those surfaces as well.
Where hard lubes run into trouble is in the intermediate pressure/temperature ranges of +P loads. There are greater needs for lubrication in these velocity ranges than in the range for “standard” revolver loads (i.e. 16,000 CUP and 850 fps). However, current hard lubes generally melt very little in this range, so the only lube pumping mechanism is still simple displacement by the lands. Since very little of the lube has melted, it can’t play much of a role in bore sealing and significant leading is commonly encountered with loads in this ballpark that are lubed with hard lubes.
Most American shooters are devoted magnum fans, and so they push commercial hard-cast bullets at full-house magnum levels, and the hard alloys and hard lubes do just fine in this ballistic regime. There are also quite a few bullseye shooters running .38 WCs at 725 fps and these commercial offerings do just fine in this regime as well. Where problems are encountered is in the +P range, around 1000-1100 fps. The 6-2 alloys, with their Brinnel hardness of 20 or so, are too hard to obdurate at intermediate pressures, and the hard lubes are not effectively melted or efficiently pumped in this pressure regime, so the bore sealing process breaks down and severe leading can result. Shooting oversized bullets may help, but probably not much because this leading is caused primarily by variations in the land/groove width, and once the bullet is swaged down to groove diameter in the forcing cone it is subject to all of the same variations that a groove diameter bullet would be subjected to. Softer alloys and/or softer lubes are the key to success here.
Not all of the hard lube has to melt to lubricate, only partial melting is needed, so when a shooter tells you that a hard lube is no good because he’s recovered bullets from the backstop that still had lube in their grooves, he’s raising an interesting observation, but one that needs to be looked at in more detail because only part of the hard lube has to melt to effectively lubricate the bullet’s passage, some may very well be left behind (and wasted). What we really need is a formulation for hard lube that doesn’t melt to a liquid phase, but rather undergoes a pressure-induced transition to a plastic phase that demonstrates moderate viscous flow.
Molybdenum disulfide. Molybdenum disulfide is an excellent dry (i.e. solid) lubricant with exceptional chemical and thermal stability. Moly coating bullets and barrels has gotten a lot of press in recent years. For jacketed bullets, Moly coating is claimed to reduce metal fouling, reduce barrel erosion/wear, increase barrel life, lower pressures, allow the use of more powder for higher velocities, and protect the bore against oxidation. Some of these issues may well apply to cast bullets, others may not. So the question arises does Moly coating a cast bullet provide any of the same advantages as Moly coating a jacketed bullet? If so, how do we best apply Moly coating to a cast bullet?
Two issues need to be remembered, bullet lube serves to lubricate the bullet’s passage and it also serves to help seal the propellant gases behind the bullet’s base. A dry coat of Moly can contribute somewhat to the first issue, but can do nothing for the second. What’s more, while a dry coat of Moly is highly adherent to a metal surface, it’s only a fraction of a thousandth thick. Therefore, if it gets damaged or abraded away, there is nothing left to do either job, and dry Moly coat cannot be pumped from one spot to another like a soft lube can be. The net result is that a dry Moly lube can be useful for those loads that have modest lubrication demands and do not require the lube to actively support the sealing operation, i.e. relatively low pressure loads. In non-magnum applications, dry Moly can provide entirely adequate performance, assuming a good, smooth bore. Lee’s tumble lube, which paints a thin coat of “lubricant” over the entire bullet’s surface in a thin coat of varnish, operates in much the same manner, and with much the same limitations. Both of these lubricants fail when used in a revolver with a significant barrel/frame constriction.
However, if Moly is incorporated into a traditional soft lube formulation, then the benefits of both the soft lube and the Moly are obtained. The soft lube lubricates the bullet, is pumpable and goes to where the leaks are and helps to seal the propellant gases. It also serves as a carrier for the Moly and helps to deliver it to the bore surface, where little by little it forms an adherent coating that protects against adhesion of lead fouling and oxidation. So how does soft Moly lube stack up against Moly coated jacketed bullets? Well, in both cases the Moly clearly serves to reduce metal fouling. In terms of barrel erosion/wear, cast bullets are already considerably more gentle on throats and bores than are jacketed bullets, and I doubt that Moly can really do much of anything to improve on that situation. Likewise, it is doubtful that Moly lube does much to lower pressures with cast bullet loads since relatively little energy is required to engrave the projectile to begin with, and my personal experiments have revealed little velocity difference between Moly lubed cast bullets and those lubricated with more traditional soft lubes. So in conclusion, many of the benefits obtained by the jacketed bullet rifle shooter are lost to the cast bullet handgunner, but the elimination of metal fouling is clearly a benefit shared by all. In a sense, shooting Moly-lubed cast bullets is bore conditioning at its finest.
Sizing/Lubing bullets. Sizing and lubing cast bullets is the act of pushing a cast bullet into a steel die that is the desired diameter (and round, which many cast bullets are not as they fall from the blocks), and then lubricant is forced into the lube grooves, either concurrently, or in a separate step. Before we get into the details of sizing, a decision must be made as to what size you want the bullet to be, and therefore which sizing die to buy, so let's address that first.
For the subject of this book (cast bullets in handguns) there are basically three different classes of handgun that we need to consider -- revolvers, single-shots and semi-autos. As a general statement, the fastest road to good accuracy with cast bullets it to size the bullet to fit the throat (if there is one). For a revolver, you want to size the bullet fit to the cylinder throats. You don't need any special gauges or tools to determine this, just find out what size bullet will pass through the throat smoothly and snugly. You can use either jacketed bullets or cast bullets for this test. This will commonly be about .001" over nominal groove diameter, but not always, so see what fits (and shoots) best in your gun. If your revolver's cylinder throats are smaller than the groove diameter, then you might want to consider opening them up to match the barrel.
For a single-shot (like a Contender) size your bullets to fit the barrel throat, this can be as much as .003" over groove diameter (e.g. .311" for a .308" barrel). Making a chamber casting is really helpful for this determination, but if you aren't set up for that, then you can drop an oversized (and unsized!) cast bullet into the throat and give it a light smack with a hammer and piece of wooden dowel, then knock it back out and mic it to see what the throat diameter is on your barrel. I generally aim for about .001" less than actual throat diameter to insure ease of chambering.
In the case of semi-autos, the way these guns are chambered there isn't really much of a throat at all, so I generally size these cast bullets for nominal groove diameter.
Sizer dies. You can use RCBS sizer dies in a Lyman sizer, and vice versa, but Star sizer dies will only work in Star sizers, and Saeco sizer dies will only work in Saeco sizers. Some of the really old Lyman/Ideal sizer dies were made with a step inside the sizer die so that they shaved the bullets down. I don't like these dies as they can distort a bullet upon sizing (if I come across one of these dies they get chucked up in my lathe and tapered very quickly). Newer sizer dies are all tapered and swage the bullet to size. This works very well.
Sometimes old sizer dies have been abused and can be scratched. Scratched dies will give you scratched bullets, so take a close look at old sizer dies before you buy them. A light polish will generally clean them right up. Many of my sizer dies are older than I am and are still going strong.
Nose punches. Nose punches fit the nose of the bullet and keep it centered as it goes into the sizer die (assuming that your sizer is square, and while most are pretty good, a few individual sizers are out of square....). These are generally made by the bullet mould manufacturers to fit the exact nose profiles of their respective moulds, and are available for a few dollars. Since the vast majority of my handgun cast bullet shooting involves flat-pointed bullets, I have cobbled together a short-cut that works pretty well for me. I've made myself a couple of "universal" flat-point nose punches which allow the flat-nosed bullets to self-center in the sizer die by trapping them between parallel planes (this approach doesn't work for bullets smaller than about .30 caliber, but for .32 caliber and above this works pretty well). This allows me to use 2 different universal flat-point nose punches (one about .300" diameter, and a second about .350" diameter) for virtually all of my bullet-sizing chores. (I still use regular nose punches for round-nose bullets).
Lube-sizers. Again, Lyman sizer dies can be used in RCBS sizers, and vice versa, but Saeco machines only use Saeco dies, and Star sizers only use Star dies (the Star sizer is available through Magna), etc. Lee push-through sizers fit into a standard reloading press and offer the advantage of being a nose-first (i.e. self-centering) system that does not need different nose punches for different nose shapes. The Lee system is intended for their tumble-lube. I'm not a big fan of tumble-lubing as it puts lube in all kinds of places where it does no good, and it doesn't put very much lube where it IS needed, but the Lee sizing system is a clever idea for getting bullets the right size, round and square to the base.
Lyman/Ideal has been making lubrisizers since the 19th century, and their tools have used the traditional way of sizing/lubing a bullet -- push it down into a sizing die, squeeze lube into the lube groove(s), then pull the sized/lubed bullet back up out of the die. Lubrisizers from RCBS and Saeco use the same basic principles. This is a simple and straightforward process, but it involves 2 separate strokes of the press to size/lube a bullet (not to mention that the operator has to remove the sized bullet manually). While perfectly adequate in terms of the quality of final product, the overall process can be somewhat slow in practice. This has led folks to try other designs in an effort to speed things up. For example, Lee Precision has come with a clever sizing method that uses sizing dies that screw in to a standard reloading press and have a container to capture the sized bullet as they come out the top of the die. This allows the caster to use equipment that he (or she) already has, and has the added advantage of being nose-first sizing (i.e. self-centering and doesn't need separate nose punches for different bullet profiles). The Lee sizer has no provision for lubing the bullets, but they have addressed that by inventing their Lee Liquid Alox Bullet Lube and the Tumble Lube method. In short, the sized bullets are coated with an Alox containing varnish and allowed to dry, then loaded normally. Some folks really like the Lee tumble lube method. The Lee sizer is probably the most affordable sizing tool available today.
Another clever approach to speeding up bullet sizing was reduced to practice by Star. In the Star lubrisizer (now available through Magma Engineering Company, PO Box 161, 20955 East Ocatillo Road, Queen Creek, Arizona, 85242, (602)987-9008) the bullet enters the sizing die nose down and the ram is pressing on the bullet's base. After the bullet is sized, there is no need to remove the bullet as it passes all the way through the sizing die and out the bottom. By placing a small shelf below the sizer and putting a box on that shelf a caster is able to size a lot of bullets in a hurry, and they all go straight into the box waiting below. The Star system is a very fast system, and being a nose-first sizing system it allows the bullet to self-center and you can use the same ram for all bullets of the same caliber (i.e. no need for separate nose punches for different bullet shapes). Perhaps the only drawback of the Star system is that it requires a certain amount of "tweaking" to make sure that the lube only goes where you want it, and not all over the rest of the bullet. The Star sizer is one of the more expensive sizers on the market, but those folks who use them tend to go to great lengths singing their praises, and about the only time you see one on the used market is when an old caster passes away and his estate is being liquidated. Folks don't tend to let go of Star lube-sizers voluntarily...
I have used many of the lubrisizers available (RCBS, Ideal, Lyman, etc.) and I must confess that my primary tools are a pair of old Lyman 450s, both equipped with Midway heaters, one typically set up with whatever commercial hard lube I may be working with at that time, and one set up with my homemade Moly lube. I have an extensive set of sizing dies (Lyman, Ideal, RCBS, unknown and custom) to fit these sizers and see no reason to retool to another format. These two sizers have sized many, many thousands of cast bullets each, and will likely still be going long after I'm gone. I have a third Lyman 450 that I picked up at a gun show for cheap, sitting on the shelf above my sizing bench just in case I need a back-up, but so far all it has done is accumulate dust.
Commercial lubes. There are all kinds of bullets lubes available to the bullet caster today. Some are brightly colored, some are soft and gooey, and some are hard as a rock. Which ones work best? Well, let's take a look....
The traditional favorite for smokeless cast bullet loads is the old NRA Alox formula. Back in the 1950s E. H. Harrison, working on the NRA's American Rifleman staff, set out on a detailed, systematic study of cast bullet lubricants, and this formulation was the final product of all of his research. This lube is simple made by using equal parts (by weight) of beeswax and Alox 2138F grease (a lithium based grease used in automotive applications). This lube has been used for decades and has come to be the landmark by which all other bullet lubes are judged. Javelina, RCBS, and Lee lubes (as well as several others) use this basic formulation. It is a very good lube for general purpose cast bullet shooting and will handle all of the shooting chores that a revolver shooter will have.
SPG is a special formulation of soft lube that is put together specifically for black powder shooters (but it can be used with smokeless loads too). It helps to keep BP fouling soft and helps to preserve the accuracy potential of the rifle and load. SPG is arguably the best BP lube out there (although there are also some homemade formulations that are also quite good).
Over the last 20 years, with the growth seen in the commercial cast bullet industry, the prevalence of hard bullet lubes has increased significantly (e.g. Thompson, Rooster, Apache, etc.). Commercial bullet casters want to be able to ship their bullets to their customers and not have to worry about the lube being smeared all over everything when they arrive. Thus, a hard bullet lube, that forms a solid ring of lubricant in the lube groove, stays in place and doesn't smear readily during handling or shipping has become the standard of the industry. New casters, seeing all these gaily-colored hard lubes on commercial wares, commonly go with hard lubes when they start casting their own thinking that the commercial casters use the hard lubes because they offer some ballistic advantage that the soft lubes don't. While they may paint a glorified picture of the performance these lubes will deliver for the shooter, the main reason they are using these hard lubes is to avoid customer complaints from using a messy lube. That's not to say that hard lubes don't do a good job, in many cases they perform superbly. For example, for many years I used various commercial hard lubes for my bullseye target loads, and I shot thousands and thousands of .38 wadcutters in practice and in competition with these hard lubes, all with complete satisfaction. Similarly, for many years I used a commercial hard lube for all of my magnum revolver hunting loads (circa 1400 fps), with zero complaints. These loads were accurate, clean and easily assembled. However, when I went to put together mid-range loads for these same guns using the same bullets at 1000-1100 fps, there were times that I got leading so severe that I couldn't see the rifling after only 6 rounds! In a number of other cases there were no overt leading problems, but accuracy was so poor that not all my shots even hit the paper at 25 yards! As a result of these mid-range experiences, my fondness for hard lubes has waned somewhat. Hard lubes can be very good, but soft lubes are far more versatile, particularly in mid-range loads.
Hard lubes require some sort of heater to warm the lube up so that it can flow through the lube-sizer. These heaters come in a variety of sizes and varieties, but there is a cute little base-plate heater marketed by Midway that works very well for this application (I've had two for over 15 years, and like them). For folks that would rather cobble together their own solutions, I understand that but some hard lubes can also be softened suitably with a 100 watt light bulb placed right next to the lube-sizer.
Homemade lubes. Making your own bullet lube is one of the oldest traditions in shooting. Pretty much everything that was slimy, gooey, greasy or smoky has been tried as a bullet lube at one time or another. In the early days it was mainly things like bear fat or deer tallow because those were the only greases they had available. In more recent years folks have incorporated all sorts of high tech lubricants into bullet lube like fluorocarbons, various polymers, or exotic Polynesian waxes. Flow and consistency is very important for a bullet lube, so homemade recipes tend to include both lubricants (e.g. greases and oils) and stiffeners (e.g. waxes and polymers), and in some cases mixing agents (soaps and surfactants). Occasionally, a component can serve multiple roles (e.g. lard). We've already talked about the NRA Alox formula, and mixtures of beeswax and grease are in general a good starting point for bullet lube (as described above, beeswax has a number of very desirable properties for bullet lube in terms of plastic flow range, most waxes don't work as well as beeswax in this role), but what other combinations work well?
My friend Charles Graff has been making his own bullet lube for decades and his preferred recipe is simply a mixture of beeswax and Vaseline (which is petroleum jelly, not a lithium or aluminum-based grease) in approximately a 60/40 ratio of beeswax to Vaseline (this recipe is based on achieving a particular consistency, not exact weight ratios). Charles reports that he has used this lube for all of his handgun cast bullet shooting for 50 years, and that it has served admirably.
Recently, in cast bullet circles "Felix lube" has taken on almost mythical attributes. Competitive target shooters report unequalled accuracy is possible with Felix lube, and hunters report that they can achieve much higher velocities using Felix lube than they can with other lubes. Everybody who uses Felix lube reports that barrels remain shiny and clean, with no leading. So, what is "Felix lube"? It is the creation of Felix Robbins, a master caster that has been an active cast bullet experimenter for many years who has shared the fruits of his research and his optimized bullet lube recipe for others to use. Making Felix lube is a somewhat complicated process, but it results in a product that is very highly regarded. With no further ado (this recipe was taken from the Research and Data section of http://www.castpics.net/):
Heat mineral (baby) oil until it starts to smoke. Add castor oil, and then raise the heat until the smoking level is again approached while continuously stirring for at least a 1/2 hour. Grate the soap, or very finely sliver it, and then barely add it into the mixture until all of it is thoroughly melted. Now, add the carnauba wax slowly, again raising the heat until just below the smoking level. After the Caranauba is well mixed into the solution, add the beeswax while maintaining the heat level high. Finally, reduce the heat of the mixture to about 125F, using a thermometer when available. Add the lanolin while stirring continuously until the whole shootin' match is homogenous. Lanolin is extremely sensitive to heat during the mixing stage, but not otherwise after the mixture had been cold for a while and the mixture (new lube) reheated for modification(s). The lube can be re-melted effectively using a microwave, and then poured into a lubrisizer.
Adding paraffin to the batch makes it a harder pan lube, or it can be used when beeswax is scarce. A special ingredient which impresses friends is the Carnauba wax. It's not required to do the job, but it keeps the barrel mirror bright after each shot. The next time a cheese shop is visited, pick a selection having a thick "plastic" looking wrapper. The Laughing Cow brand comes to mind. After enjoying the cheese, wash off the cover and mash up about a rounded teaspoon (not tablespoon) and melt this into your freshly made lube. Also, Maker's Mark whiskey has the same type of sealer and can also be used for it's carnauba content.
A little more info on this lube -- beeswax is the base, castor oil is the real lube, lanolin makes the lube sticky (viscosity), sodium stearate glues the mess together so it does not separate into components upon cooling, carnauba wax adds the shine, and paraffin is the ultimate hardener, only to be used as a last resort. Add more castor oil to make the lube slicker for smaller bores and/or a winter lube. There are also variants of Felix Lube made with peanut oil and Dexron III automatic transmission fluid, but the bottom line is they all work well.
Actually, reheating the lube multiple times improves its shooting qualities. This is because castor oil requires polymerization with the other ingredients to prevent a leaking lube. Polymerization is a function of both time and heat level, and this is why there is a minimum 1/2 hour requirement at the highest heat level without the production of smoke.
Favorites. Invariably the question arises as to what our favorite bullet lube is. Well, this is one case where our tastes diverge. Rob swears by the old Lyman "black goo". While there is no question that "black goo" is a very good bullet lube, I have never liked the almost Vaseline-like consistency, or the mess that I inevitably make when working with it. But the bottom-line is that it goes through a lube-sizer with ease, prevents leading very effectively and delivers very good accuracy.
Personally, my favorite is my homemade Moly lube, made from equal parts by weight of beeswax (either yellow or white, color doesn't matter) mixed with Sta-Lube Extreme Pressure Moly-Graph Multi-Purpose Grease. This grease, like Alox 2138F, is also a lithium-based grease, so this lube is basically just a variant of the old NRA formula for Alox lube, with a little molybdenum disulfide and graphite thrown in. I have used this lube in loads that operate from 500 fps to over 2300 fps, and it has worked well in all of them. This lube is easily handled (i.e. not overly tacky/messy), flows smoothly through a lube-sizer, and delivers good accuracy. In addition, it helps to condition the bore by laying down a little bit of Moly with each shot. I have found that over the course of testing a wide variety of diverse load combinations that sooner or later, even with the best of lubes, one stumbles across evil-tempered loads that lead up a barrel. If the bore has this Moly conditioning, then these leading deposits don't stick as steadfastly and are easily cleaned up. This lube is also quite affordable to make -- between beekeeper friends and clearance sales at auto parts stores, I am pretty much set for bullet lube for life (and all for less than $20)
Making lube. In order to mix beeswax with anything, you have to be able to melt the wax in a controlled fashion. Done over direct heat (i.e. on the stove) this is invariably a smoky process and one that will likely get you in trouble with your Better Half (do not use any of her cookware for this process!). One solution is to perform this maneuver on a camp stove outdoors. Another solution is to boil water on the stove and heat your lube mixture in the boiling water (like a double-boiler). A friend of mine related a slick solution that he has used for years -- he mixes his lube components in a mayonnaise jar and melts them in the microwave and pours the melted lube directly into his lube-sizer. I tried this and was amazed at how well it works -- no smoke! I used this method for a couple of years and then had the mayonnaise jar break in the microwave during heating, and make a big mess, so I switched over to 1-quart canning jars (tempered glass to handle the heat better). This worked fine for another couple of years, but eventually I had one of these break in the microwave too, so I moved to a thick-walled Pyrex measuring cup, complete with a convenient handle and pour spout for pouring the melted lube into the lube-sizer (bought at the grocery store for less than $2). Ultimately, this shattered too, so I have moved over to using a ceramic coffee mug to melt my bullet lube in the microwave now. I have friends that use hot-plates, old coffee pots, even a Fry-Daddy deep-fryer to melt their lube; there are lots of ways to do it.
Summary and conclusions. Cast bullets require lubrication to prevent leading. Bullet lube serves not only to lubricate the passage of the bullet down the bore but also to seal the propellant gases behind the base. One of the most important properties of this lubricant is that it must be able to flow to be most effective. This property allows lube to be pumped to the bullet/bore interface by a variety of mechanisms. The shape of the lube grooves (i.e. either beveled or radiused) are not overly important, as both are able to effectively pump the lube to the bore. Hard lubes need to melt partially before they perform their best as lubricants, soft lubes simply flow in their native state, and as a result are more versatile. Lubes that form a hard film (for example either dry Moly or Lee’s tumble lube varnish) can only lubricate the bullet, they can’t flow and form a seal, and these lubes therefore have their effectiveness limited to lower pressure loads. Putting Moly into a soft lube formulation combines the advantages discussed for of all the above bullet lubes.
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