RELOADING
Reloading is the act of taking a fired shell casing, returning it to its original dimensions while simultaneously removing the spent primer, repriming the case, placing the carefully measured, appropriate amount of the appropriate type of smokeless powder in the case, and reseating a bullet. The result is a ready-to-fire cartridge.
Pistol cartridges are reloaded in much the same manner, but with variations from the procedure used for bottleneck rifle cases. This article will focus on reloading bottleneck rifle cases.A good discussion with pictures and illustrations, as well as descriptions of equipment and methods is available at http://www.rcbs.com/guide/default.aspx
What follows is simply a general introduction to reloading. Many readers who understand reloading may wish to skip directly down to the second section, entitled ACCURACY.
This procedure can be done with very simple and inexpensive equipment. If you limit yourself to cartridges which were fired in the single rifle you are loading for, a Lee Loader is a complete reloading outfit in a single small box. I mention reloading for a single rifle, using cartridges already fired in that rifle, because the Lee Loader resizes only the neck of the cartridge. A factory-loaded round is made to dimensions so that it will chamber in any rifle which has standard dimensions, plus tolerances, of the particular caliber in question. That is, any factory made round in a given caliber must be small enough in diameter and short enough in length to chamber in any rifle of that caliber, which may, by design and stated standards, be larger or smaller than another rifle in that caliber.
If you go to the shooting range, carrying your Remington 700 bolt action 30-'06, and pick up an empty 30-'06 case from the ground, there is a significant chance that empty case will not chamber, or at least not easily chamber in YOUR 30-'06. It may have been fired in a Browning or Remington semiautomatic rifle, and semiautos are known to commonly have chambers just a tiny bit on the large side of the standard, for ease in the automatic process of chambering and extraction. And high quality bolt guns are known to have chambers just a tiny bit on the small side of the standard, for the precision expected from a high quality bolt gun.If you fire a case, extract it, and attempt to rechamber that case, just fired from your rifle, it will fit perfectly. It has expanded with the pressure of the burning powder to precisely fit the chamber it was fired in.
The Lee Loader takes advantage of this, by only resizing the neck of the case, the part which holds the bullet. It removes the vast majority of the serious force required to resize the entire case, and enables a compact, very portable package for all the equipment and pieces parts needed to reload one caliber for one gun. And this neck-sizing-only operation actually contributes to accuracy, since the fired case perfectly fits the chamber, and the undersized factory or full-length-sized case actually lies on the floor of the chamber, slightly off center.The drawback is, this neck-sized-only cartridge may not fit another rifle. A friend, though he may have a 30-'06 as well, might not be able to use your reloaded ammunition. Or this ammunition may not fit another 30-'06 which you own.
If you choose the more standard type of reloading practices, you will need a 'press', a device with a lever and compound mechanical advantage, which aligns the components and the forces to enable a more strenuous effort. In full length reloading, the bottleneck rifle case is first lightly lubricated, taking particular care to not get any lubricant above the shoulder of the round-- that is, no lube allowed to get on the sloping shoulder of the case. Under pressure, oil on the shoulder can be forced into a single drop, and that drop can deform the shoulder under pressure.The process forces a slightly overlarge brass case into a slightly undersized steel die. This requires force. The mechanical advantage of the press makes the required force manageable by even small and weaker individuals.
Then, often, just as much force is required to pull the case out of the die. A specific 'shell holder' locates the case on the movable ram, and the die is carefully located in a threaded hole above the ram's travel.The process described actually serves several functions. The case walls are brought back to near-factory size, the position of the shoulder on the case is 'set back', and the neck size is reduced beneath the dimension required to accept a new bullet. At the furthest insertion of the case into the die, a rod extending through the center of the die punches out the old primer. And, upon withdrawal, in the typical die, the rod through the middle also is equipped with a 'button' of a very precise diameter, which when drawn back through the slightly undersized neck, opens the neck out to the precise diameter needed for a new bullet to be inserted.Full length resized cases will fit any standard chamber of the given caliber.
These cases can be used in any rifle of the given caliber. But there is a down side; to make the case 'shrink', the leftover diameter 'has to go somewhere'. Where it goes is forward; the case 'grows' in length. And this growth 'takes away' thickness down close to the head, the primed end, of the case.
So, to maintain tolerances, the length of the resized case must be precisely measured, typically with a dial micrometer or a 'fixture', a type of die perfectly sized so that any case which is too long will protrude a bit of the neck out of the die. There are many ways of reducing the length of cases. It may be done on an adjustable, relatively inexpensive type of 'lathe' made for the purpose, and is adjustable to accommodate whatever caliber and length is required, with a cutting head which shortens the case by shaving material from the end of the neck. Others use other methods.
Lee, again, makes one of my favorites, a shell holder and a fixture for it are chucked up in a standard electrical drill, and a rod precisely locates a cutting head so that the case can only be reduced to the specific appropriate length. Every separate caliber has a specified shell holder, and a specific rod to properly locate the cutting head for that caliber.Some calibers do use the same shell holder. For instance, a 45 ACP pistol case, a 30-'06 rifle case, a 308 rifle case, a 22-250 rifle case all use the same shell holder. And there are many other calibers which use this same shell holder... and many which use different ones. Sometimes, rarely, a caliber requires a shell holder unique to that caliber.But when reloading using full length resizing, the inevitable growth of the case must be monitored. And, as well, the thinning of the brass case, internally, near the head of the case must be monitored. Usually a bright line will begin to develop around the case's circumference, near the head. As this thinning progresses with every successive full length resizing operation, it becomes more likely that the case will fail, or have the head pulled off the case when attempting to extract it from the chamber after firing. This requires, typically, driving the remainder of the case from the chamber with a wooden dowel or other appropriate tool, taking great care to not mar or damage the rifling in the barrel, nor the polished metal of the chamber. This can be most embarrassing, to say the least, if you need a followup shot on your deer, or your target otherwise needs servicing with another round. Under the best of circumstances, it is a royal pain. In the worst of circumstances, it could cause you to die.
Prudence then dictates that you should form 'batches' of brass cases, well marked and segregated, kept properly trimmed, and closely monitored. It may turn out that with your die and your gun's particular chamber dimensions, this inevitable (with full length resizing) growth and thinning dictates that after the third... or fourth... or fifth... or whatever resizing operation, the cases be retired. Perhaps they are not yet 'critical'... but you do not want to use 'marginal' components. Clearly mark them, and retire them. Perhaps, in some future time, it may be necessary-- in extreme, and i do mean extreme circumstances, to load them one more time. Of course, the obvious down side is, if you are in an extreme situation, the last thing you need is marginal or untrustworth ammunition.... yet I can't bring myself to simply discard.
A variant of neck sizing uses a standard die, but the die is adjusted so that only part of the neck is reduced, and little reduction is made on the case diameter below the neck. This helps reduce the growth and thinning of the case. It also helps towards being able to use the ammunition thus produced in other guns, but it is possible and even likely that the cases still will not function in another gun of the same caliber.Loading for one rifle, keeping that brass and those loaded cases strictly separate, and neck sizing only goes great lengths towards allowing many, many, many reloading cycles for any given piece and batch of brass.I speak of 'batches' of brass. Every experienced reloader knows that not all brass is created equal. An experienced hand will feel the difference among Federal, Remington, Winchester, Hornady cases, and military cases. So, when building a box of cartridges, do go to great lengths to not mix 'headstamps'. And go to greater lengths to not mix once fired with twice fired with thrice fired cases. Keep your batches separate and unique.I prefer Federal. Others swear by Remington. But the different manufacturers products are different, and behave differently as they go through the reloading process.
Repriming the cases is likely the most 'dangerous' of the operations involved in reloading. While smokeless gunpowder is a very high-energy chemical, it does not 'explode'. It burns, at a very fast rate. But primers, of necessity and by their nature, ARE explosive. And they are astoundingly powerful, and potentially destructive, for such tiny things.Most reloading presses are equipped so that the priming operation can be accomplished during the first step of reloading, the resizing operation. Typically, this arrangement is such that, after the depriming and resizing operation, a movable fixture which is designed to have an individual primer on its tip is swung in under the deprimed case, and the ram is used to lower the case onto this fixture, seating the primer. The fixture is then swung out of the way, and the case taken to the bottom of the ram's stroke and removed, making way for the next case.I do not like this 'ram priming', or press priming. Again, Lee, manufactures a little gadget to be placed in the large threaded inline hole in the top of the press, where dies are normally placed. This allows the priming of the case on the ram upstroke, where there is most mechanical advantage and most 'feel'. Properly and repetitively seating the primers, each and every one, is an important, even critical part of manufacturing your own very accurate ammunition. This Lee 'Ram Prime' will do it, but it is a bit clumsy to set up, and attention must be closely paid in order to properly employ it.
My favorite is a device made by RCBS, but I fear it may be discontinued. It uses an attached side tray which keeps the primers open side up, and feeds one primer at a time into the hand-squeeze powered ram to seat primers in an unprimed case, held in a shell holder on top of the device. It provides excellent 'feel', allowing a very repeatable priming process. It is a Hand Prime, but I cannot locate it on the RCBS web site. It should be at Midway, or other large commercial retailers.
After priming, the powder is placed in the case. It needs to be carefully measured, the powder carefully chosen, and strictly observe 'max loads' of any given combination. I cannot stress this too highly. Don't get careless and use 'Number 7' pistol powder instead of 'Reloader 7' rifle powder. You will have an explosion right in your face. There are many, many ways to hurt or kill yourself, or others, reloading with due care and attention to all the rules.Powder can be measured, as Lee Loader does, by various, little, carefully sized 'spoons'. Or a 'powder measure', which employs variable volume chambers to 'meter' powder. And some weigh each charge of powder for each case. This is a step where grave mistakes can be made. Exercise due caution, and use your best judgment.
If 'something doesn't look right', there's a good chance it isn't right. 'Measure twice, cut once'. For a mechanical scale, the RCBS 5-0-5 is excellent.Lastly, you seat the bullet, which is another die/press operation. You want to carefully measure the overall length of the cartridge you manufacture. If it is too long, it may not fit in the magazine for your gun. Or if it is too short, it can produce unwanted spikes of high pressure, from reducing the case volume by the base of the bullet.In truth, so far in this article, I have largely been reinventing the wheel.And excellent listing of reloading equipment is available here:http://www.rcbs.com/guide/default.aspx
Likewise, on that same site, there is an excellent pictorial representation of reloading. Further, if you are going to reload, even one caliber with a Lee Loader, it would serve you very well to purchase a good, recognized reloading manual. Lyman publishes an excellent one, several in fact, but you will be looking for 'centerfire'. Lee, Sierra, Hodgdon, Speer, Hornady and others publish excellent reloading manuals, some available on CD, and on line, for a fee. I found the Sierra manual most appropriate for my daily reloading chores, Lyman the best for the writeup on reloading.I will touch on one more problem you may encounter. If you buy or obtain brass from military surplus, you will find that many of these cases have specially designed primer pockets, by which the primers are positively retained by a circle of metal flashing around the primer pocket, and this metal flashing is flattened down over the inserted primer. 'Crimped'.Standard depriming, while perhaps more difficult with these 'retained' primers, can still be accomplished.
However, the resulting deprimed case will usually have an interference with the metal flashing around the primer pocket, and it is retained. And it usually will interfere with inserting the new primer. So, the first reloading of military cases often requires the use of either a 'primer pocket swager', a die-like device which flattens the sheath into the pocket and forms it to proper diameter. A more direct method can be employed, simply by using the 'pointed end' of a 'chamfer tool'. This can be seen at the RCBS web site, and on the web sites of anyone handling reloading equipment and supplies.
This tool is designed for removing roughage from the case mouth after trimming, and is pointed on one end, with three short protruding fingers on the other, for inside and outside deburring, respectively. It works well to remove the 'crimp' material from military cases. Not all military cases have crimped primer pockets; some are lacquered, as are, occasionally the junction of the case mouth and bullet. Lacquered primers require no special effort.
ACCURACY
Now we come to what I really wanted to speak to. And that is, reloading to produce the most inherently accurate ammunition which can be produced. Commercial ammunition production is done on automated, very high speed, motor driven machines. There is no individual supervision of any step, nor of any cartridge. It is sort of presumed that this ammunition, from a good rifle, should be capable of shooting with 2 minute of angle accuracy. This translates to approximately 2 inch groups at 100 yards.
With carefully assembled handloads, that can be cut to a half an inch groups at 100 yards-- presuming that the shooter and the rifle are up to the task. And if you really, really do it completely and correctly, that half inch can approach a quarter of an inch accuracy at 100 yards. But the gun and the shooter must be equally high quality.
The first step for me, in loading for extreme accuracy, is to get a large batch of brass. I have stated that I prefer Federal. I do take great pains to insure they are either 'new brass' from the factory, or 'once fired' from commercial outlets. I first full length resize, and deprime all the brass. Let's say, 100 pieces.Then I trim and chamfer (de-burr) them all to a stated minimum length. If any pieces are grossly long, or grossly short, set them aside for batches not requiring such great accuracy, or aside as 'only for emergency use'.
Then weigh them each and all. Use a Sharpie marker and number each. Keep a good notebook and record all the weights. This task is much easier with an electronic scale. Re-zero the scale often. A line powered, rather than battery powered scale will produce more reliable results over the long haul, for the consistency of the power source, the utility power, and that batteries lose power as they are used, which can cause the zero to drift.You will see, after doing 100 cases, that typically they will fall into 'groups' of pretty similar weight- within a few grains of each other. There will be, most likely, a few heavies, and a few lightweights, far outside the norm. Don't use those far out of norm for your super-accurate ammo.
Now, if you like, you can do statistical analysis on the brass, spreadsheet analysis, and pick groups for consistent standard deviation, mean weight, whatever. But simply choosing batches of 20 from similar weight cases works pretty derned well. If you're really into this, you may then find an appropriate and consistently-applicable 'plug' for the primer hole and pocket, and for the case mouth. You then carefully fill, each precisely the same, each case with water or antifreeze. Antifreeze, because it is more dense than water, and thus volume variations produce more weight variation. By weighing each case, filled precisely the same, plugged with precisely the same utensils, you are actually comparing the volume of each case. Most should be relatively close, within a very few grains. Any obvious serious deviations should be devoted to the 'less than great' case group.
Now carefully rinse the cases, and place them in a very low (200F) oven on a very clean cookie sheet, or carefully and thoroughly dry them by some other fairly low temperature means-- sunlight for an extended period, a central-heat vent for an extended period, whatever you have. Make absolutely sure they are absolutely dry.
Then you proceed to 'deburring' the primer flash hole, on the inside of the case. These holes are punched at the factory, and invariably there is leftover ragged metal on the inside of the case. There are many brands of tools for this purpose. This link illustrates one such, and of necessity they are all similar.http://www.redding-reloading.com/pages/flasholetools.html
Don't try to bore a hole through the primer pocket; simply light rotational pressure slicks them up nicely. This greatly aids in consistent ignition.Next you will 'uniform' the primer pocket. Machine-formed primer pockets, while within tolerances, are never perfectly round, nor perfectly deep, case to case. And for superior accuracy, the one thing most important is uniformity in ALL things. Primer pocket uniforming tools are available on line. One size is for large rifle or pistol primer pockets, the other size for small rifle and small pistol primer pockets.
They are a small cutter head on some sort of hand held tool, sometimes able to be placed on lathes, manual or motor driven. Federal cases, I find typically, when the pockets are 'uniformed' will show bright cut brass on the walls of the pocket, as well and bright brass almost to the center of the pocket where the flash hole is. Typically, on Federal cases, the flash hole is a tiny bit deeper than the rest of the pocket. This is of little consequence, unless there is some gross variation. This uniforming process produces a perfectly sized pocket, with 90-degree, square edges where the wall meets the floor of the pocket. Seating primers is thus much easier, not for the pocket being more loose, bigger, but for the consistency of drag as the primer is inserted in the pocket, and the perfect 'landing' when the primer reaches the square-edged bottom.
You will find with practice this becomes absurdly simple to determine. And with the 'extension rod' of a dial caliper, you should find the same depth below the face of the case head to the top of the primer after insertion. A very few thousandths of an inch.
Next we will consider 'neck turning'. Commercially produced brass may be 'mass produced good', but almost invariably you will find a variation in case thickness around the circumference of the neck. These variations make the case mouth 'grip tighter' on one side than on the other. Turning the case necks, inside and outside produces a consistent wall thickness all the way around. Typically for outside neck turning, a cutting fixture will be set with feeler gauges to produce the minimum of removal of metal all the way around. You can start with a stated wall thickness-- for instance, 0.012 inches, 12 thousandths of an inch. It may or may not produce bright metal all the way around the neck. For our purposes, intermittent low spots, just barely low, which leave brass untouched by the cutting head is acceptable. This leaves the maximum amount of brass in place for strength.
There are various tools for this task. Some cut inside and outside simultaneously. If you are serious enough about accuracy and reloading for accuracy, I strongly suggest that you investigate your options, perhaps participate in shooters' discussion boards, and find a workable way to do this 'turning' operation.
The last task before actually assembling components is annealing the cases. You want the heads of the cases to remain strong. The heat treatment applied, and reinforced with ever shot keeps that brass hard. But for consistent results, you want the case necks and shoulders to be brought to the same hardness, stiffness, and this is accomplished by annealing.
To anneal a case, I use a case spinner fixture, as discussed above in the Lee case trimming device. The spinner is chucked up in a drill, an appropriate shell holder, proprietary for this Lee device, is threaded onto the chuckable spinner, and a case tightened down.Take a propane torch with a medium, well defined steady flame, and set it on its base. Spin the case with the drill, and bring the 'heat line' down from the neck and just over the shoulder. Have a largish container of cold water handy, and instantly after removing the spinning case from the heat, release the case from the shell holder on the spinner and let it fall into the cold water, quenching it.
This produces a 'zeroed' condition of heat treat, you do this a batch at a time at the initial processing of the brass. All the brass so treated, and placed in the same batch, will be subjected to the same number of firings, which involves a rapid heat and slow cool. Every shot fired rehardens the brass, but it does so in a consistent matter, piece by piece in your batch. So the batch remains together metallurgically.
One final step. When bullets are seated in cases to factory specification and standards, when you chamber a round, there is a small gap between the bearing surface of the bullet and the rifling of the barrel. This results in a small 'jump' from case mouth to barrel rifling. By using neck-sized-only ammunition, the case is self centering in the chamber. That helps keep everything consistent, shot to shot. But you can further enhance this by very lightly neck sizing a case, loosely fitting a specific brand, type, and weight of bullet into the case mouth.
Let's say, for illustration, you are loading Sierra Gameking 165 grain boattail spire points into a 30-'06 case. I use a Lee collet-and-mandrel style neck sizer, so it is easy to neck it down just enough to provide minimal grip on the bullet. Seat the bullet in a seating die, and seat it long enough, far enough out, to be certain to encounter the rifling when chambered. Measure it the overall length. This is your starting point. Blacken the bullet tip up to the flat-side, the surface which bears on the barrel rifling. Chamber the round, then carefully extract it. DO NOT USE A PRIMED CASE NOR CERTAINLY NOT A POWDER-LADEN CASE.
Examine the exposed bullet under good light and with good magnifying or reading glasses, and you will see the marks made on the blackened bullet by the rifling. Measure the overall length again, it has almost surely been shortened, since the neck is not really tight. Reblacken the bullet, rechamber, extract. You should just barely see marks from the rifling. If seriously marked, use the seating die to very slightly, just a very few thousandths per iteration, as indicated by the marks produced by the rifling. That is your guide to how much shorter the round needs to be. Your object is to produce a piece of ammunition where the seated bullet just barely touches the rifling when chambered. This measurement and adjustment is only good for the specific rifle, and the specific bullet manufacturer, style, and weight being used. ANY variation means re-measure.
Keep good notes, soon enough you will have a length for 150 grain Sierra Gameking boattail spires, one for their 165 grain Gameking boattail spires, etc.There are some calibers and guns which cannot be done this way, particularly for the length restrictions of the magazine. The one which comes first to mind is the 300 Winchester Magnum. For 180 grain boattail Nosler Ballistic Tips, specifically, the bullet to touch the rifling needs to be longer than the magazine can accommodate. So you are left with no choice but to seat to the maximum overall length allowed by the magazine, or single-load the too-long assembled cartridges.The methods I describe above have produced magnificently accurate ammunition which will consistently shoot well under a minute of angle.
William Michael Kemp
"Mike Kemp"
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