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Case Preparation and Reloading by Charles Griffis Hitting where you’re aiming repeatedly and reliably with a production rifle, using ammunition loaded by you, is a real turn on. The secret is a bunch of little things that go toward consistency and consistency is what makes accurate ammunition. How do you get this consistency in reloads for a production hunting rifle? Start by purchasing commercial cases in quantities of 100 the same brand with the same lot number. Check all cases and cull any with obvious imperfections, such as cracks, severe dents, or off center flash holes, etc. Off center flash holes are among the more obvious, yet insidious faults. Off center flash holes seem to have little influence on accuracy until the groups are consistently under one half minute. (One half minute is about one half inch at one hundred yards, one inch at two hundred yards, etc.) However, cases with off center flash holes have a tendency to bend, break, and otherwise wreak havoc with the decapping pin in most resizing dies. Also, when the decapping pin goes through the off center flash hole, they can move the expander ball off center creating necks that are not straight. Cases with necks that are not straight will adversely affect accuracy. The next two steps, primer pocket uniforming and flash hole deburring probably have more effect on improving the consistency of hunting caliber ammunition than anything else you can do in the case preparation process. For these steps, I recommend the carbide White Tail designed Primer Pocket Uniformer and the K&M Flash hole Deburring tool. In the manufacturing of cases, most times the primer pockets are pressed into the case head and the flash hole is punched through the base. This leaves a slight radius, sometimes uneven, seldom exactly the same depth, to seat the primer against. Also, when the flash hole is punched, it leaves a burr on one side. Many times this burr is large enough to affect ignition. To obtain uniform and consistent ignition, the primer pockets must all be the same depth and the bottom of the pocket must be flat. Also, the burr inside the case must be removed from the flash hole. Primer pocket uniforming and flash hole deburring are a definite aid in obtaining uniform primer pockets and, consistent flash hole diameter and length. These two steps are much more important than deciding on the brand of press or dies. After you have reamed the primer pocket to a uniform depth and removed the flash hole burr on the new cases, you are ready for the next step -- full length resizing of the cases. For hunting rifles with big game in mind, I recommend you always full length resize the cases. When choosing a press, try to get the stiffest, heaviest, single stage press available. This type press is best when accuracy is the primary goal. If kept clean and lightly oiled, both the press and the dies will give many years of trouble free service. The selection of the 7/8" X 14 standard sizing dies will do quite fine, however, the use of Benchrest Competition Type standard 7/8" X 14 seaters, those with floating chambers will support the bullet better while seating. These Competition type seating dies with floating chambers are available from a number of good die manufactures and work very well in the standard press. These special seaters cost a little more, but if you really want the extra bit of accuracy they are well worth it. Nezt, we turn our attention to the expander ball. Many expander balls have a sharp edge on the top side, this is the side that enters the case neck first after sizing, and can shave brass from inside the neck. This edge should be tapered to help reduce this shaving and center the expander ball in the neck. This can be accomplished by securing the expander ball in a drill and, being careful not to reduce the diameter, taper with a file and polish with 0000 (four ought) steel wool or fine sand paper such as 600 Wet-or-Dry. With the press of your choice mounted securely and everything cleaned and polished, we are ready to mount the die in the press. To align the die properly, remove the expander ball and deprimming pin. Screw the die body into the press. Do not tighten the retainer ring at this time. Insert the proper shell holder, lubricate some of the rejected cases from steps above, and begin to adjust the sizing die. Insert a case in the shell holder, and operating the press handle, adjust the die body until the neck is sized to the neck shoulder junction. I like to size as much of the neck as possible on my hunting ammo. If you are resizing cases that have been fire formed in your bolt action rifle, remove the firing pin from the bolt and chamber this fired, but not sized case. If there is a slight resistance upon closing the bolt this is good. After you size this case, chamber it again. If it goes in without any resistance, you may be sizing the case too much, creating headspace problems. If so, you may need to back off the sizing die about one eighth turn and repeat this test with another fired case. Using a new rejected case, size the case and while the case is fully inserted into the die, tighten the die retainer ring. With the retainer ring tight, we are reasonably sure that all cases will be sized the same. Using a few of the culls you saved from previous steps, lubricate both the external surface of the entire case and inside surface of the neck portion of the case. These cases will be used to adjust the expander ball. The cases you have used to adjust the die body without the expander ball installed, have a greatly reduced neck, and may buckle when trying to force the expander ball into these cases. Do not try to salvage these cases, they should already be culls, and now is the time to discard them. Remove the case from the die and install the expander ball. Using a new rejected fully lubricated case, adjust the ram to the fully sized position. (Usually this shows about the thickness of a credit card between the die and the shell holder.) When retracting the case, adjust the expander ball to a position where it will enter the case neck just before the case neck is free of the neck portion of the die. Once this adjustment is made, tighten the expander ball retainer ring. If you adjust the die with the expander ball in this position, the depriming pin usually cannot be used to remove the primer. Remove the depriming pin and throw it away. This will reduce the chance of moving the expander ball off center and also allow proper die adjustment. Pay special attention here, for more cases are warped out of alignment when resizing than at any other step in the reloading process. Be sure the press is sturdy enough to have no lateral movement in the ram, and check for alignment between the ram and the die. Also, be aware that the stuff that goes into making primers will act as fine grinding compound and will introduce premature wear into your press and dies if not removed first. Use a hand tool to remove the spent primer, and always clean the pocket with the Primer Pocket Uniformer tool before running through the sizing die. This helps keep the die clean and reduces the frequency of the need to polish the die. Once everything is adjusted and tight, lubricate all cases, including inside the neck. Two good case lubricants are Lee Case Lube and Imperial Sizing Die Wax. They are easy to apply, work great, leave no residue when wiped off and seem to cause fewer hydraulic dents than many others. You can apply these lubes on the outside of the case with the fingers and inside the neck easily using Q-tips. After lubricating, size all the cases being sure everything stays tight. When all cases have been sized, you can wipe the lube off using a lint free cloth or wash in HOT soapy water. After cases are run through the sizing die, they are often too long and should be trimmed to length. Use some of the sized culls and set the case trimmer. Many reloaders find the shortest case and trim all other cases to the length that cleans up the shortest case. In any event, be sure to trim all cases to the same length. When trimming, use just enough pressure to keep the trimmer cutting without taking off too much at a time. Regardless, if you take off a lot of material or none at all, you should always chamfer the outside and the inside of every case. After chamfering, use a bore brush inside the case neck and steel wool on the external portion of the neck to remove powder residue and any other gunky buildup. Some feel that case segregation by weight is a waste of time. Some feel it is very important. If you feel it will help, it probably will. Most agree that as much as one and one-half percentage variance has little effect on accuracy of match ammunition, even greater tolerance for hunting ammunition. Weighing cases, if done at all, will have more effect if done at this time, after the excess metal has been removed. When you are satisfied that the cases are clean and void of all sizing lubrication, or anything else that might contaminate the propellant, it is time to seat the primer. Here is where I differ with the designers of most reloading presses. You should never use the press to seat primers. Too much leverage and can crush the primers causing erratic ignition. The parts on the reloading press that are designed to seat primers should be removed and thrown away. This means that other ways of seating the primer must be used. The only safe way is to use one of the fine hand priming tools. One of the best single stage priming tools I know of is made by K&M and is sold by many of the dealers listed at the end of this article. There are a number of good priming tools on the market and, as with most business dealings, you get what you pay for. RCBS and LEE both make good priming tools of the "Auto-prime" design. To use these "Auto-prime" tools, you just dump the whole box of (100) primers into the tray, shake, and all the primers are turned right side up ready to use. Put the lid on and began the priming operation without ever having to touch the primers with your greasy fingers. There is a lot written about developing a "feel" for seating primers. The only real thing to remember about seating primers is push them in until they hit bottom, then don’t push any more. Remember, it is easy to put too much pressure on the primer and they could be crushed, causing erratic ignition. Too little pressure and you have raised primers. Raised primers can cause erratic ignition, and sometimes even prevent the round from chambering. Neither raised nor crushed primers are conductive to good accuracy. If you have followed directions so far, neither raised or crushed primers should ever be a problem. The case is now ready for us to put in some powder. If you are serious about reloading, buy an arm full of reloading manuals, and read these manuals. Reloading manuals contain a world of good information. Take the time to learn what these manuals have to say. If you are not serious, please do us all a favor -- TAKE UP GOLF. If you are semi-serious, find a good mid-range load in a good manual and never vary this load. Don’t experiment unless you know what you are doing. Check the reloading manuals for suggestions about a starting point, and heed the advice about starting below MAX and working up. This can not be taken lightly. If your load shows signs of pressure, back off, even if you are somewhat below maximum. Each rifle is different, and some will handle a larger powder charge without developing unsafe pressure, while others.... Study the stuff in the front of the manuals and know about such things as slow powders or fast powders, magnum primers or standard primers, etc. Be extremely careful about light loads with slow powder. Especially, know the signs and causes of excessive pressure, and what to do about them. Know about headspace. Heed the warnings about not using G I cases. When loading rifle cartridges, usually the best accuracy can be obtained with a powder that is a tad fast, while sometimes the fastest load is developed using a powder that is a tad slow. Also, the best accuracy is usually obtained when the case has minimum air space. This means the best load is with the case full. These are just general guidelines and are not cast in lead. (Or concrete, or stone or whatever things like these are cast in.) After we choose the powder, we should decide if we will always weigh each charge or use a measurer. It might help to know that nobody at a benchrest match weigh the charges they use. Some benchrest shooters may weigh a few charges of a new batch (lot) of powder to set the measurer, then use only the measurer to throw the charge. After the initial weighing of a new batch to set the measurer, using a scale is a tedious waste of time, especially if you use the any of the small grain powders. Since the records show that benchrest shooters, who never weigh charges during a match, and often put five bullets in one hole that measures less than .10 inch more than the bullet diameter, we should realize that there is something to be said about measuring charges. For consistency, charging by volume is every bit as accurate as charging by weight and lots more fun. (Meaning lots less work.) If using a measurer is new to you, practice throwing charges until your variance is less than .2 grains. The trick is consistency of technique. Operate the handle the same each time. Maintain a constant powder reservoir level, usually between one third to full. You will soon realize that after setting the measurer, weighing really is a waste of time. As to the brand, there are quite a number of good powder measures on the market. Two measures that come to mind are Neil Jones’ "Custom Products" and the Redding BR-30. These two measures have micrometer adjustments and are reliably repeatable. If you are loading only one caliber and only one bullet weight, any number of measures will fill the bill. Regardless of brand, it is recommended that a powder bottle adapter that includes a built in baffle be used. Lets assume our new hunting rifle is a bolt action Ruger, Winchester or Remington , in .308 Winchester. These are all very good choices for any deer class big game. (There are others that are also very good, but there is just so much room.) Next, we will choose the 150 grain Nosler Partition soft point bullet. The 150 Nosler because it performs very well on game, can be made to shoot accurately, and most reloaders are familiar with it. This bullet can be made to leave the muzzle at about 2600 to 2800 feet per second. This is the range of velocity given in most reloading manuals for the 150 grain bullet in the .308 Winchester. With the knowledge that we can get the best accuracy using a powder that is slightly on the fast side, we select H4895 or W-W 748. The only difference I can detect between H4895 and IMR-4895 is the smaller grain size of H4895, allowing the HODGDON stuff to go through the measurer easier. W-W 748 is a ball powder and goes through the measurer even better. You can take real advantage of using a measurer by loading at the range. Take the resized primed cases, some powder, the measurer, some bullets, and your press with seating dies to the range. If you have purchased one of the $150.00 to $200.00 plus measures you can vary the powder charge at the range. If you have one of the good, but not repeatable (not micrometer adjustable) measures, be sure to set it at home before you go to the range. A major factor when using your powder measurer is be sure to mount the measure solidly. When filling the powder reservoir, don’t just dump the powder in and start throwing charges. To do so could create inconsistent charges. It is best to cycle a few, say five to ten charges through the measurer before we start loading cases. After shooting for a while, when we return to the measurer, again we need to cycle a few charges before we began loading. Begin testing by loading only three cases at a time and test this load. When you think you are close to the best load, with the best seating depth, load five rounds and test. Be sure to visually inspect each and every case loaded to verify there is the same amount of powder in each case. The real advantage of loading at the range, in addition to varying the powder charge, is the ability to vary the seating depth of the bullet. Many of the finer dealers sell the Chamber-All OAL Gauge, a Bullet Comparator, and a good stainless steel dial caliper. These will allow you to find the setting at which the bullet just touches the lands. The general rule for seating different calibers is ".30 caliber into the lands, .22 caliber back off the lands about .010 inch and those in between are unique unto themselves." That means you will have to experiment to find the best seating depth. Experience shows most all calibers will shoot best when the bullet is just touching the lands. Use a good steel dial caliper and comparator to measure the bullet seating depth. A difference of .005 inch will make a real difference, so be sure to try different seating depths to find what your rifle prefers. Seating depth can have more effect on group size and shape than a full grain of powder. Try loading ten rounds at one setting, and varying the powder by as much as a full grain, load another ten rounds, and still a third ten rounds set another grain. If the seating depth is what the rifle likes, usually all groups will be the same size and shape, probably at different points of impact, but no real difference in group size or shape. Use caution when seating the bullet. If the bullet is seated too far into the lands, excessive pressure may reach dangerous levels. Also, unless the rifle is a single shot, the length of the loaded round may not feed through the magazine. If this is the case, your seating depth may be dictated by the magazine length. For best efficiency, do not allow the bullet to intrude on the powder space, if it does, use a lighter (shorter) bullet. Weighing bullets from good manufactures is like weighing cases, if you think it helps it probably does. However, segregating bullets by bearing length is a definite aid to good accuracy. Some very good bullet manufactures may have two or more lengths in a single box, usually indicating different lots or produced on different machines. Segregate bullets by bearing length, not overall length, and it will be easier to keep things consistent when finding the correct seating depth for the loaded round. To determine the bearing length, use a comparator and a good dial caliper. With these tools, it is possible to find where the bullet will touch the lands when the loaded round is chambered. This is very important when reloading for accuracy. Measure the distance from the base of the bullet to the point where the ogive and the body of the bullet meet, giving the bearing length. Segregation according to this measurement helps assure uniform depth of the base of the bullet in the loaded round when the bullet is seated to a length where it just touches the lands. Remember when we said chamfer the outside and the inside of every case? This sequence, outside and inside helps reduce the tendency of shaving metal from the bullet when the bullet is seated. Shaving metal from a bullet will cause accuracy problems, and reducing accuracy problems is what this is all about. Again, use just enough pressure to cut the edge smooth, just enough to remove the burr left by the trimmer without over doing it. Now, you are ready. Test enough to know what settings for powder and bullet to use to obtain the level of accuracy you desire. As suggested, start low and work up gradually. Always look for any signs of excess pressure, and back off if you notice anything unusual. If you want the maximum velocity for hunting, be sure you test in the same conditions in which you will hunt. Pay special attention to temperature. A safe load developed in January will not be the same when used for prairie dogs in July. When you are satisfied, record everything. Always record everything and you will improve much faster than trusting it to memory. By now you probably realize that loading for accuracy is no big thing, but a lot of little things all aimed at consistency. Good luck. This is a small list of some of the fine suppliers of precision reloading tools.
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