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Lanolin-based pump spray lubes are available from Dillon and Frankford Arsenal. \u00a0 You can also make your own using anhydrous lanolin (available from online suppliers) and 90% isopropyl alcohol (gas line anti-freeze) in a 1:10 ratio.<\/p>\n
If you instead decide to use a non-evaporating liquid lube (such as with a lube pad), be careful not to leave any droplets of liquid on the case neck or shoulder because the liquid will create dents in the cases during sizing.<\/p>\n
Headspace<\/b>
\nBefore we get into setting up the sizing die, we need to discuss headspace and cartridge headspace length. \u00a0 Headspace in a firearm is defined as the distance from the breech or bolt face to the part of the chamber that stops the forward movement of the cartridge when it is inserted into the chamber. \u00a0 For rimless bottleneck rifle cartridges (like .223, 308, and .30-06), the part of the chamber that stops the forward movement of the cartridge is the angled portion that contacts the shoulder of the case. \u00a0 The cartridge headspace length is the distance from the case head to the part of the case on which the cartridge headspaces. \u00a0 For a rimless bottleneck rifle cartridge, this is a point on the shoulder of the case.<\/p>\n
The difference between the chamber’s headspace and the cartridge headspace length determines the amount of extra fore-and-aft ‘room’ the cartridge has in the chamber. \u00a0 If there is too little room (because the cartridge headspace length is too long for the chamber), the bolt will not close and the firearm will not go into battery. \u00a0 Too much room (because the cartridge headspace length is too short for the chamber) can result in inconsistent ignition, poor accuracy, short brass life, or catastrophic case head separation. \u00a0 In other words, if you get the cartridge headspace length wrong, the ammo will not shoot at all, will shoot badly, or will blow up. \u00a0 Therefore, it’s quite important to get the cartridge headspace length right.<\/p>\n
Measuring Headspace Length<\/b>
\nThere are two common tools available – The RCBS Precision Mic and the Hornady Headspace Comparator – that allow you to measure cartridge headspace length. \u00a0 The Precision Mic from RCBS (Figure 2) is a self contained device that is sort of a specialized hollow micrometer. \u00a0 To use the Precision Mic, you unscrew the top, drop in a case, and screw the top back on until it contacts the case shoulder. \u00a0 There are graduations on the side of the device that allow you to read the headspace length of the case compared to the SAAMI “0” distance for that caliber. \u00a0 The RCBS Precision Mic is caliber\/cartridge specific. \u00a0 If you want to measure the headspace length of the .308 and .30-06, you’ll need two different Precision Mics – one for each caliber. \u00a0 RCBS makes Precision Mics for dozens of common calibers. \u00a0 They cost $40 to $50 each.<\/p>\n
<\/p>\n The Hornady Headspace Comparator Set is used in conjunction with a dial or digital caliper. \u00a0 To measure headspace length with the Hornady Comparator, you attach the bushing holder to one jaw of the dial caliper, then install the caliber-appropriate bushing into the holder. \u00a0 The bushing has a hole with a diameter that is larger than the case neck, but smaller than the case body. \u00a0 You place the neck of the case to be measured into the hole on the bushing, and close the caliper until it contacts the case head. \u00a0 The resulting measurement will show you the distance from the case head to a point on the shoulder of the case. \u00a0 (See Figure 3).<\/p>\n <\/p>\n The Hornady kit costs about $40. \u00a0 It comes with 5 bushings that allow you to measure the headspace length on 100’s of different cartridges. \u00a0 Instead of measuring to SAAMI “0”, the Hornady gage gives you a relative measurement of the case headspace length. \u00a0 As you’ll read below, a relative measurement is often enough.<\/p>\n Setting up the die<\/b> We’ve already discussed how to measure the headspace distance on the case, but how do you measure the available room in the chamber? It’s simple – measure the headspace length of a case that was fired from the rifle. \u00a0 When a bottleneck cartridge is fired, it fire-forms (expands) to take up all of the available space in the chamber. \u00a0 The sides and neck expand, the shoulder blows out and the case stretches to take up all of the available headspace. \u00a0 Simply measure a fired case using the tools (either the Precision Mic or the Hornady Headspace Comparator) described above. \u00a0 Before setting up the sizing die, measure and record the headspace distance of a case fired from your rifle. \u00a0 Subtract the appropriate amount (0.003″ to 0.006″ for a semi-auto, lever or pump action, 0.001″ to 0.003″ for a bolt action of single shot) to determine the “target” measurement for your sized case headspace length.<\/p>\n To initially set up the die, follow the instructions that came with the die. \u00a0 Typically, they’ll instruct you to install the shell holder, and then screw the die into the press so that the shell holder cams against the bottom of the die when the ram is raised all the way up. \u00a0 Do not lock down the die when you do this. \u00a0 Using a permanent marker, draw a witness mark on the die at about 6:00 (see figure 4). \u00a0 This will act as a reference mark to allow you to arrive at your final settings more efficiently.<\/p>\n <\/p>\n Take a clean, lubed, fired case from your rifle, place it in the shell holder, run it through the sizing die, and measure the headspace length. \u00a0 It will almost certainly be shorter than your target measurement.<\/p>\n You’ll need to back out the die slightly to increase the headspace length of your sized cases to match your target distance. \u00a0 This is where your witness mark comes in handy. \u00a0 Standard reloading dies have 14 threads per inch; so one complete turn of the die will move it vertically 1\/14th of in inch (about 0.071″). \u00a0 Picture the circular die as the face of a clock, and your witness mark at 6:00 as the hour hand. \u00a0 If you were to move the witness mark from 6:00 to 5:00, you would back out the die about 0.006″. \u00a0 Studies have shown that most people can discern the time to within 15 minutes just by looking at the hour hand. \u00a0 If you can do this, you’ll have the ability to adjust your die height (and case headspace length) in 0.0015″ increments using your witness mark.<\/p>\n Adjust the height of the die, run another clean, lubed, fired case into though the die, and measure it. \u00a0 Continue to adjust the die until you reach your target case headspace length measurement. \u00a0 Tighten the locking ring on the die (without moving the witness mark) and run one more case though it to verify that you have it set properly. \u00a0 With the die locked in place, your cartridge headspace distance is set. \u00a0 It shouldn’t move during use, but if it makes you feel better, you can re-measure every so often to ensure that you’re still on the money.<\/p>\n PLEASE NOTE: The above procedure assumes that you are using cases that were last fired out of the rifle for which you are loading. \u00a0 If you are setting up the die using mixed brass or range pickups, first measure the headspace length of the fired unsized cases that you will use for setup to ensure that they start out longer than your target case headspace length. \u00a0 If the cases were fired from a rifle with a chamber shorter than your rifle, backing out the die will not increase the case headspace length of an already too-short case.<\/p>\n In some rare cases when using a single-stage press, the headspace length of the sized case will still be too long even when the die is bottoming out hard on the shell holder. \u00a0 While the part of the shell holder that attaches to the ram is standardized (so that it will fit in any standard press), the height of the shell holders is not standardized. \u00a0 Some are taller than others. \u00a0 This problem can be avoided by using a shell holder from the same company that manufactured your dies. \u00a0 If you’re stuck with a mismatched set, you can reduce the height of your shell holder by placing a sheet of 400-grit silicon carbide wet\/dry paper onto a flat surface (such as a piece of glass) and lapping the top of the shell holder in a figure-8 pattern.<\/p>\n It’s critically important to set the shoulder of the case to where it’s supposed to be. That shoulder acts as a gas seal, preventing plasma hot gases from leaking past the case, and eroding your chamber. The knuckles and joints of your reloading press have tolerances which allow the press to operate. Unfortunately, when you lube a brass rifle case, and introduce it into the full length resizing die, the friction is sufficient to stretch the joints of the press to their extreme limits, which will create a gap between the bottom of the sizing die, and the top of the shell holder. That gap will be the amount that the shoulder isn’t pushed back to it’s dimensional location. The fix is to make one further adjustment of the sizing die in the press. The Expander Ball<\/b> Cases from different manufacturers will vary slightly in case wall thickness. \u00a0 To ensure that the neck of every case processed by your sizing die has the same inside diameter, the reloading manufacturers design the dies so that the portion of the sizing die that reduces the diameter of the case purposely makes the neck undersized. \u00a0 When the case is extracted from the die, a part of the decapping mandrel called the expander ball is drawn though the neck to increase the diameter from the inside. \u00a0 This ensures that the inside diameter of the necks of your resized cases will be the same regardless of the thickness of the case walls.<\/p>\n In many dies, the expander ball also acts as the nut that holds the decapping pin to the mandrel (see figure 5). \u00a0 You should never resize cases with the expander ball removed. \u00a0 Some reloaders that decap the cases prior to sizing will run them through the resizing die with the entire decapping mandrel removed. \u00a0 This is a mistake. \u00a0 The resulting cases will have necks with varying inside diameters, all of which will be too small.<\/p>\n<\/a><\/p>\n<\/a><\/p>\n
\nThe goal in setting up the full length sizing die is to set the die so that it pushes the case shoulder back far enough so that the cartridge will reliably chamber, but no farther. \u00a0 The height of the die in the press will determine the distance that the shoulder is pushed back. \u00a0 For semi-auto, lever action, and slide (pump) action rifles, you’ll want the cartridge headspace length to be 0.003″ to 0.006″ shorter than the chamber. \u00a0 You can make it a bit tighter for bolt action and single-shot rifles, with the cartridge headspace distance only 0.001″ to 0.003″ shorter than the available room in the chamber.<\/p>\n<\/a><\/p>\n
\nLower the ram\/shell holder a bit, and adjust the sizing die a slight bit further in. Do this with no brass in the shell holder. This will create what I call an OVERCAM situation in the linkage of the press. The result will be a very tight pressure between the bottom of the die and the top of the shell holder. The previous gap will no longer be evident. And, the shoulder will be pushed into it’s proper location.
\nAt the beginning of this discussion, I mentioned rifle dies not having carbide inserts. This over camming situation becomes all important with regard to carbide inserts. While the carbide inserts are hard, they are also brittle. If you were to do this over camming setup with a carbide inserts rifle die, you risk breaking the carbide insert. So, don’t try the over cam with a carbide insert type die.<\/p>\n
\nWhen extracting the sized case from the die, you will feel resistance as the case initially frees itself from the die. \u00a0 As you further raise the handle to lower the ram, you will feel almost no resistance for the next inch or two of ram travel, followed by a noticeable period of additional resistance just as the case is fully extracted from the die. \u00a0 This final bit of resistance is caused by the expander ball being pulled through the case neck. \u00a0 The expander ball is necessary to ensure that your case necks all have a consistent inside diameter regardless of the thickness of the case.<\/p>\n