Worst Case:	Good Case:	Best Case:

Worst Case: The bullet shows severe signs of gas cutting. Slight groove engraving can just be seen on the front driving bands, but all signs of the grooves on the rearmost band have been abraded. Such loads can be expected to give serious leading problems and accuracy will fall off very quickly after several rounds have been fired.

Good Case: The bullets show clear groove engraving on all driving bands from front to rear. Slight gas cutting can be seen on the rear band and is confirmed by bullet diameter measurements in this area. No gas cutting could be detected by diameter measurements in front of the lube groove. The width of the groove engraving on the front driving band is wider than at the rear, indicating a mismatch of alloy hardness and chamber pressure just after powder ignition. This could be due to one or more reasons which will be discussed later. Nevertheless, accuracy with such loads should be good and leading minimal.

Best Case: This shows the ideal situation, no sign of gas cutting or alloy yielding to chamber pressure. This ideal set-up might be difficult to achieve in practice without resorting to some tricks better known to the dedicated cast bullet shooter. I admit to resorting to one of these tricks and actually used a powdered shot buffer  (similar to Buffer Mix #47 from Ballistic Products Inc.)

     The four major ways of controlling gas cutting are as follows:

• Bullet Fit see previous chapter 6.6.8 by Norman F. Johnson.
• Bullet Hardness  see previous chapter 6.6.8 by Norman F. Johnson.
• Powder Selection
• Bullet Selection

     The four items mentioned above are listed in descending order of importance based on my experiences gained over the last 20+ years.

Powder Selection: Before selecting a particular powder from a reloading manual we should have a fairly clear picture in our minds as to what happens after the firing pin strikes the primer. As the powder charge burns, the gas pressure builds up and the force acting on the bullet’s base causes the bullet to move forward after the moment of inertia is overcome. As the bullet progresses along its path it makes contact with the grooves of the barrel and is forced to rotate about its own longitudinal axis. The strain on the bullet and its acceleration is directly related to the gas pressure and reaches a maximum as the chamber pressure peaks. The question, whether the bullet can successfully withstand this ordeal is not just a question of alloy strength, but also where the bullet is as the chamber pressure peaks. A fast pistol powder will mean that the pressure will peak before the bullet has travelled very far. Depending on the seating depth and length of the bullet on the one hand and the chamber’s throat on the other, this could mean that the bullet has only just started to engrave the rifling as the pressure peaks. It is the area of bullet/groove contact which has to take the strain caused by the acceleration of rotation (Ref. 1 and 2.). Sticking with the example of the 180 grain PBTC in the .357 Mag. bullet travel at P max. will vary according to powder charge and type.

Fast (like N320) = 0.3-0.4” (powder charge 4.3 to 5.4 grain; P max. 18,600-28,200 psi) Medium (like 3N37) = 0.4-0.5” (powder charge 6.0 to 7.5 grain; P max. 18,000-28,600 psi) Slow (like N110) = 0.4-0.5” (powder charge 13.5 to 14.5 grain; P max. 27,900-30,600 psi) Source: QuickLOAD software from Hartmut Broemel, Babenhausen, Germany.

     Generally, fast powders are used for plinking and target loads, whereas the slow powders are used for hunting and maximum loads. Even when considering target loads, it is worthwhile considering powder burn rates somewhere between fast and slow. Slower powders will not only achieve a given velocity with lower pressure, but also allow an increase in bullet/groove contact before P max. is attained. This can be very beneficial if the target bullets are made from a soft alloy or even of the hollow-base variety. Often the low charges of fast powders in target loads can burn “dirty”. A change to a heavier charge of a slightly slower powder can eliminate this niggling effect.

     Here in Germany most of the major shooting associations require certain power factors for centre-fire handgun events. The trend is definitely leaning towards the heavier bullets combined with medium burn powders. Powders like the N340 and 3N37 are becoming very popular and are often be used in a wide range of calibers from 9 mm Luger through to .44 Rem. Mag. Even some shooters are using these powder types in the .45 Auto with good results.

Bullet selection: The discussion in this paragraph will be limited to bullet form and weight and not touch on bullet hardness since this has been reviewed already. The most popular bullet forms for hand gunners are the semi-wadcutters(SWC), round nose(RN), roundnose-flatpoint (RNFP) and the truncated cones(TC). All of these bullet forms can be used for accurate loads, although in certain guns a particular weight and form will work better than others. A good starting point for cartridge length is .010" under maximum permissible length with this gun and bullet and not the maximum length written in the manuals. This helps to ensure that bullet /groove contact is optimised during powder burning. There might be some exceptions here, especially in semi-auto pistols where a longer cartridge length might be permissible from the chamber dimensions, but will not fit in the magazine and/or cycle properly. Of course trying to maximise cartridge length can be difficult when using shorter and hence lighter bullets. The seating depth with such bullets might not be sufficient to give consistent combustion, especially when using anything slower than fast powders. I think it is appropriate to make sure that bullets are seated to more than .250" into the case. Usually accuracy is easier to achieve with bullets with a short nose section and having a wider front driving band. The short nose section helps promote the ratio of bearing length to overall length and a wider front driving band has more flesh so to speak and is useful as the bullet begins its travel into the grooves and lands.

     In loads where a certain power factor is required and successive shots need to be fired quickly, heavier bullets have an edge over lighter bullets. The recoil tends to be more tameable and the gun doesn’t kick so high allowing a quicker/easier recovery of the sight picture. Competitive shooters here in Germany are going more for the 140/150 grains in 9MM; 170/180 grains in .357 Mag. and 300 grains in .44 Rem. Mag. Gas check bullets are not really necessary for target shooting if the bullet “fits” and the chamber pressure and alloy strength are well harmonised. If there is any mis-match for these conditions a gas checked bullet can work wonders in controlling the level of leading during a shooting session. On the other hand soft gas checks or shot buffers can also be used with similar effects.

     In working up an accurate load there might be some signs of bullet tipping on the target - small crescents can appear around the shot holes. This could either be, that the bullet diameter is a tad too small or that the velocity was not high enough to stabilize the bullet. The latter cause is more likely with longer bullets being fired at distances of 50 yards and more. Try sizing bullets larger to start with and if problem still exists try increasing powder charge. Alternatively, switch to next slower powder to increase velocity without dramatically changing chamber pressure.

• Ref. 1. Cast Bullets by Col. E.H. Harrison (ret.) NRA publication, page 14 ’’ Is jumping the rifling likely?’’

• Ref. 2. The Bullets flight from powder to target by F.W. Mann M.D., page 368 ’’ Kinetics of spin’’.

     It is assumed that the revolver concerned is capable of decent groups with either jacketed or plated bullets to demonstrate that it is a “good-shooter” so to speak. Before starting any load development with cast bullets, check the bore diameters of the cylinder and compare this with the forcing cone diameter of the barrel. Decent accuracy can be expected with the cast bullets as long as the cylinder bores are equal or larger in diameter than the forcing cone. If the forcing cone diameter is larger than the cylinder bores accuracy will be disappointing, but it is nothing a competent gunsmith could not put right. I like to check the correct bullet diameter by driving soft, oversized bullets or round-balls through the cylinder and checking the diameter. Then confirm this by choosing a bullet with this measured diameter and then drive these bullets through the cylinder using a wooden dowel. They shouldn’t fall through freely, but should need a moderate steady force to drive them through. Make sure the cylinders are really clean before doing this test otherwise there is a good chance of misreading the results. I then like to check the maximum cartridge length with this bullet/gun combo. Make up a dummy round – it goes without saying of course no powder or primer Having chambered the dummy then measure and note the distance from the tip of the bullet to the front face of the cylinder using a digital calliper. Then insert a naked bullet into the same cylinder and gently push forward until the bullet nestles against the cylinder throat. With the bullet held in place measure again the distance between bullet head and the front face of the cylinder. Now calculate the max. cartridge length for this gun and bullet. For initial testing choose an overall length of max. less .010".

     Unfortunately, most loading manuals do not highlight the most accurate loads, but tend to concentrate on max. loads. Sometimes they will also give starting loads. The best information can be gleaned from studying match reports and some internet sources are quite useful. Try to identify which powders are most popular with the accuracy crowd. After finding a popular load and after checking with the manuals that the load is not too excessive, make up 5 series of 5 or 10 rounds each with powders charges varying from –10%, -5% , +0% +5% and +10% of chosen load. Start by firing the rounds with the lowest powder charge first and work through to the highest charge in order to identify the powder charge giving best accuracy. In the second stage repeat the test, or fine tune the powder charges to confirm initial testing. Having done this, in the third stage we then alter bullet’s seating depth to see if accuracy can be improved some more. After finishing each shooting session check the cylinder and forcing cone for tell–tale signs of leading. If leading is occurring this does not necessarily mean that chamber pressure is too high or that the bullet alloy is too soft. It sounds like a paradox, but often the bullet alloy is too hard or chamber pressure not high enough. Sometimes switching to a softer alloy or increasing the powder charge by 5 or 10% can work miracles. If you switch alloys from say 16 BHN to about 10 BHN it is often necessary to reduce the powder charge by 5-10% to get the same accuracy as with the harder alloy.

My personal experience with 180 grain cast bullet in BHN = 16 (50% Linotype :50% pure lead) and 7,5 grain 3N37 in my S&W Mod. 27 will lead lightly after 20-30 rounds. This picture shows the leading.	In later testing I found that increasing the powder charge to 8,0 grain eliminated the leading. I now use BHN = 10 alloy ( 20:1 Pb:Sn) and accuracy was improved by backing off to 7,0 grain and no leading to boot	Just to see whether this no leading result was just a pressure effect I repeated the test with BHN = 16 bullets – surprise, surprise I still had leading with BHN = 16! See the leading in the barrel.

     For light loads where no minimum requirements on velocity or energy apply concentrate on low bullet weights (BHN range 10-16) and fast burning powders like Bullseye.

     For moderate loads where a certain powder factor is required and shooting is usually at 75 feet or less concentrate on heavier bullets (BHN range 10-16) and powders with a medium burning rate like Longshot or 3N37.

     For maximum loads at longer distances concentrate on the heaviest bullets (BHN range 16-22) with slow burning pistol powders. If accuracy is not quite there consider the use of gas-check bullets or resorting to Soft Checks or alternatively a shot buffer to eliminate gas cutting.

A Revolver And Cast Bullets

     I do not know much about handguns or casting or loading for them. Around 1970 I had a Ruger Blackhawk in 44 Magnum that I shot faithfully every weekend some 300 to 400 rounds. I spent most of my spare time during the week casting and reloading. The load was the Keith 429421 bullet in wheel weights, sized .430" and lubed with the black Lyman lube, Remington 2 1/2 primers and 9 grains of Unique. (The first time I shot that gun, first shot with factory loads, I had cuts on the web of my hand from the hammer, the top of my trigger finger and the top of my second finger from the trigger guard. Bleeding nicely from all.) I had read the Elmer Keith books, and shot a lot from a sitting position, knees up and supporting my hands and the gun, back against a tree or my car. My targets were balloons tied to rocks at 100 to 150 yards.

   At other times I've had and shot a Colt New Service in 45 Colt, a S&W M27 with 8 3/8" barrel in 357 Magnum, a M14 in 38 Special, the obligatory Luger and many other revolvers and auto-loading pistols.

     A few years ago I bought a nickel-plated well-used M29 with an 8 3/8" barrel and a Simmons 4X scope. I experimented with this revolver and several bullet molds, keeping good records of what I tried and the resulting accuracy.

     Summary-Here's what I think I know: Bullets much smaller than the chamber throats lead the barrel on revolvers. Lead in revolver barrels decreases accuracy. Proper size or oversize bullets eliminate leading, and are the easiest way to solve the leading problem. CF Ventures Soft Gas Checks and Cream of Wheat (COW) fillers eliminate leading, at least for slower velocity loads; and shoot with reasonable accuracy. Slower powders reduce leading. Faster loads shoot more accurately than slower loads. At least with SWC bullets.

     To develop accurate cast bullet loads in semi–automatic pistols the same basic principles that apply to revolvers are used. Some pistols will not function properly with all bullet forms. Usually, it is the short nosed SWC’s which can cause problems in as much as the action will not cycle flawlessly. Sometimes altering the bullet seating depth can help, if in doubt make up some “dummy“ rounds and cycle the action manually. A good easy way to check the bullet diameter is to insert the cast bullet nose first into the chamber of the barrel, push forward until it rests firmly in the throat. Now take a small flashlight and shine it into the chamber and now look down the barrel from the muzzle end. If no light is seen, this is a sure sign that the bullet is sealing perfectly in the throat. If the chamber has a very short and sharp throat angle with hardly any free-bore to speak of, you might see some signs of light. This could be an indication that the nose section is making contact with the grooves before the bullet’s body can make an adequate seal. Examine the bullet for groove marks on the nose section. Make a “dummy” round with this bullet diameter to see if that combination of bullet diameter and case wall thickness is not going to be too tight for the chamber. It often pays to choose a slightly larger bullet diameter, then this often helps reduce the number of flyers observed on the target during the test shooting. Check the maximum cartridge length with that particular bullet and gun in a similar fashion as described for the revolver. Check that the overall length will fit into the magazine and cycle freely when the slide is operated manually. Sometimes if the ejection port is kept small, as in the case of some target pistols the unfired cartridge can not be ejected freely by manual operation. If the cartridge is simply too long, reduce the cartridge length gradually until magazine fit and cycling problems disappear.

     Usually, cartridge case volumes of typical semi-auto calibers are often smaller than the volumes of the corresponding revolver calibers. Just compare 9 mm Luger vs. .38 Spec. or .45 ACP and .45 Colt! This means that the chamber pressures will rise faster and be higher than for revolver cartridges. This is compensated to certain extent by using lower powder charges than in the revolver. But, the effects of changing the bullet seating depth can be just as significant. Seating a bullet 0.020” deeper in the 9MM. Luger can cause the chamber pressure to rise by anything from 3,000 to 4,500 psi. Comparable figures for the .38 Spec. would be about 1,000 psi! This makes it slightly more difficult to extract really consistent and good accuracy from the small case volumes like the 9 mm. Luger. This can be best done by avoiding the very fast pistol powders like Bullseye or N320 and similar. These powders are okay in the large brethren cases like the .45 Auto with light bullet weights. Similarly, for these pressure reasons the bullet alloy needs to be fairly hard say 14-16 BHN for the 9 mm. Luger. Again, with larger case volumes the softer bullet alloys of say 10 BHN can work very well.

     Locating specific load data for pistol calibers with lead bullets can be difficult. The Lyman Reloading Handbook for Pistol & Revolver is a good starting point, but it has a strong focus on fast pistol powders –at least the second Edition from 1994 does. Also, it lacks the more modern powders. Other reloading manuals tend to focus on the jacket bullet types more than the cast lead bullets. Anybody seriously interested in reloading should really consider obtaining a ballistic software product like QuickLOAD. Of course this cannot replace nor should it replace the official reloading manuals from the powder manufacturers, but it certainly helps to show and illustrate the chamber pressure curves for the various powders. The reloader gains insights to what can and will happen to pressure and velocity by switching powders or varying the powder charge. The library on cast bullets is fairly large and existing cast bullet data files can be modified and saved in a special personal bullet data files. There maybe other similar programs available in the USA, but I admit this author is biased. He is living in Germany and although he has no personal ties or benefits from the software, the designer of the software, Hartmut Broemel lives only about 1 hours drive from the author’s house.

     In working up the loads for semi–automatics watch for any tell–tale signs of leading especially if accuracy starts falling off fairly quickly. As for revolvers try increasing the powder charge by say 5% or consider using a softer alloy –at least for those large case calibers. If with either remedy the leading does not disappear or is reduced consider switching to the next slower powder. Here in Germany it is the VihtaVuori powders which tend to dominate the market and are most popular. Serious target shooters are increasingly using the N-340 and 3N37 when it comes to cast bullet loads. Some of the reasons have been outlined already and an additional reason is the trend of using heavier bullets especially where power factors are involved. Two other reasons being cited are:

a) These slower powders are often claimed as being cleaner. This is often judged on the amount of “smoke” produced at the muzzle or the cleanliness of the spent cases. This is often quoted by shooters using indoor facilities.

b) Loads with such powders are less temperamental. That is to say that small changes in reloading procedures affecting crimp and bullet seating depth etc. do not appear to have big impacts on target accuracy.

     The .45ACP 1911 was designed by John Browning to headspace on the case mouth but in fact it rarely works this way. The case head is really held against the breech by the extractor. To prove this to yourself, measure the length of a dozen .45ACP cases. You will discover that the cases are all (even newly manufactured ones) considerably shorter than SAAMI specs call for. The resultant headspace clearance would be greater than the maximum allowed, yet the ammo will shoot fine with no stretching of cases or incipient head separation, even after many firings.

     Since 1911 barrels from Colt and other suppliers are normally chambered longer than necessary, and with the additional complication of the short cases, some of us seat our bullets to a length that allows the cartridge to headspace on the bullet. This approach allows for a more consistent firing pin strike and therefore a more consistent powder burn. Accuracy is dependent upon consistent ignition more than many shooters realize; a good reason, incidentally, to keep the firing mechanism of pistols clean. Modern rifles, having a much stronger firing chain, are not quite so subject to congealed lubricants and imbedded dust.

     To accomplish the above head-spacing approach, remove the barrel from your 1911 and then alternately seat the bullet deeper into the case and drop it into the chamber until the case base is just flush with the lip that protrudes from the barrel. Do this with each bullet type that you use in that firearm and either record the OAL or keep a dummy round as a reference. If you seat the bullet too far out, the pistol will not lock up properly and therefore will not fire when the trigger is pulled.

     Some will respond that the above will call for a cartridge that is too long to properly fit in the magazine. However, the above procedure has been used by the author for about 35 years with about every bullet imaginable in approximately 14 .45 ACP barrels and magazines have accepted all without exception. As a matter of fact, in all instances, the bullet could be seated too long in its case to allow proper locking of the action before magazine interference became a problem

God Bless! Norm

"I have used the "headspace on the bullet" for the .45 ACP for over twenty years. In a five year period, I shot 75,000 rounds. The method works - my findings parallel Norm Johnson's."