Reloading: Brass Resizing

in Authors, Columns, GA Guides, Getting Started, Metallic, Reloading, Reloading Guide, Tom McHale
The resizing step does exactly what the name implies. Using a die like this Hornady .308 resizing die, you squish the fired case back into its original dimensions.

The resizing step does exactly what the name implies. Using a die like this Hornady .308 resizing die, you squish the fired case back into its original dimensions.

SERIES

Part 1: Want to Reload Your Own Ammo? Basic Questions to Consider

Part 2: The Reloading Process
Part 3: The Gear You’ll Need and What It’ll Cost You

Part 4: Brass Cleaning and Preparation to Load

Part 5: Brass Resizing

Part 6: Trimming Cartridge Cases

Part 7: Repriming the Cartridge Case

Part 8: Powder, Propellants, and Pressure

Part 9: All About Primers

Part 10: Projectiles: Materials, Weights, and Styles

Part 11: Seating and Crimping Bullets

Part 12: To Crimp or not to Crimp

Part 13: Final Inspection and Packaging Tips

Last time, we discussed ways to clean used brass to get it ready for the actual reloading process. Now, it’s time to talk about actual brass processing – getting it ready for a new primer, propellant, and projectile. The steps you have to take depend on the source of your brass and whether it’s a straight wall or bottleneck cartridge.

Sources of Brass

Depending on where you get your brass for reloading, you may have to perform from zero to several steps to prepare it for reloading. You can certainly buy ready-to-load brass that’s never been fired. The first time you load it, you usually don’t have to do anything. The brass vendor should have delivered it clean and sized and shaped to proper specifications. Of course, after you load and fire this “new” brass, you’ll need to clean, inspect, resize and maybe trim to get it back to original specifications.

Speaking of buying brass, you can also buy once-fired brass. Enterprising folks out there collect, sort, and clean brass that’s been fired at places like police and military ranges. That brass came out of a new box of factory ammunition, was fired on the range, then collected for resale, so it’s in pretty good shape. If you start your process with once-fired brass, you’ll need to inspect each piece. There’s no telling if some were damaged during its initial use. Some once-fired brass may already have the primers removed and some may not. Most of it is at least cleaned, but most of what I’ve seen still needs to be resized and trimmed if it’s bottleneck rifle brass.

Inspection

Even with factory new brass, it’s a good idea to look over each piece, even if you do so when picking it up to go into the loading press.

One of the first steps during inspection is to toss cases that are not made of brass. They're generally not reloadable.

One of the first steps during inspection is to toss cases that are not made of brass. They’re generally not reloadable.

Look for any signs of cracks or splits. If you see those, toss that case! A few cents isn’t worth the risk of a case rupture when you fire it later. I also like to look for for abnormal bulges anywhere in the brass. You might see these around the base. For example, .40 S&W cases fired from guns with partially unsupported chambers can create bulges near the cartridge case base. You can purchase push-through dies that reform brass like this, but just know that even when reshaped, that’s still a weak spot as the brass had been overworked. You’ll have to make your own call as to whether you use or toss these cases. I toss them as I prefer to operate with an overabundance of caution. I call out the .40 S&W example, but you might find bulges and significant indentations on any caliber for a variety of reasons.

If you plan to load your new cartridges to the maximum pressure and velocity range, you also might look for signs of previous overpressure situations. Does the spent primer look flattened around the edges or is the firing pin indentation all flattened around the edges? That might be a sign that the case has been subject to higher than normal pressure.

If you’re working with previously fired range brass, be picky. You don’t know the history of any given cartridge case. You’re not hooking up with just a piece of brass, but rather every previous conflagration that brass has had before. If you see signs of abuse, toss it.

Keep an eye out for brass with the "wrong" primer sizes like these two on the right. Even though they are .45 ACP cases, they have small pistol primer pockets. You can reload them, you just don't want to mix them in the same batch as regulars when adding new primers.

Keep an eye out for brass with the “wrong” primer sizes like these two on the right. Even though they are .45 ACP cases, they have small pistol primer pockets. You can reload them, you just don’t want to mix them in the same batch as regulars when adding new primers.

One more thing. I’m starting to find a lot more once-fired brass with the “wrong” primer sizes, so you’ll want to look out for that. For example, normal .45 ACP cases use a large pistol primer. Yet I see quite a few Blazer and Federal cases with small pistol primer pockets. I’ve also seen .308 Winchester cases that small instead of large rifle primer pockets. New ammo manufacturers will sometimes do runs like this so you have to look out for these anomalies. Trying to stuff a large primer into a small pocket will bring your process to a grinding halt, especially if you’re using a progressive reloading press. It’s easier to catch these flukes during the inspection step.

Should you sort your brass?

Depending on how you’re going to load, you may or may not want to sort your brass by headstamp. Different cartridge case manufacturers have slight differences in the way they make their brass. In theory, exterior dimensions and things like case mouth dimensions will always be the same. However, interior specs like wall and interior base thickness will vary. You can easily see differences by weighing a few random cartridge cases.

For example, I weighed these randomly picked .223 Remington empty cases and found the following:

Lake City: 97.0 grains
Winchester (plated): 96.9 grains
Winchester (brass): 97.2 grains
Winchester (5.56mm brass): 98.6 grains
Federal Cartridge: 95.8 grains
PMC: 96.2 grains
Hornady: 96.9 grains
Perfecta: 100.6 grains
PSD: 96.8 grains
Remington Peters: 94.8 grains

If there’s more brass material inside of one case, then the interior volume is going to be smaller. When fired, this cartridge will have higher pressure than one with a larger interior volume. If you’re loading at the maximum end of the scale, this could become an issue. Accuracy can also be affected by using different brass in any given lot. Don’t get too concerned about this for recreational shooting – the differences are usually pretty small. I did an informal test with .223 Remington a while back, using moderate loads, and didn’t see much practical difference. Certainly, if you’re shooting a precision bolt rifle, you will see a more significant variance.

For pistol brass, unless I’m trying to create some super accurate load, I don’t bother sorting by head stamp. Besides, I load most of my pistol cartridges to moderate pressure and velocity so I have safety margin when it comes to pressure.

The same rule of thumb can apply to rifle cartridges. If you’re making plinking ammo not loaded to extreme maximum pressure, there’s not much reason to sort by head stamp. If you need top end velocity or extreme accuracy, then consider loading for specific head stamps only.

Resizing and decapping

The process of resizing involves using the reloading press to jam a cartridge case into the interior of a resizing die. “Resizing die” is a fancy term for a hollow tube of metal where the inside is cut to the exact original shape of a new cartridge case. By jamming a used case, that’s probably stretched a bit, into the resizing die, the brass is forced back into its original size and shape.

This Hornady .308 Winchester resizing die also has a decapping pin that knocks out the old primer. The case on the right has already been resized.

This Hornady .308 Winchester resizing die also has a decapping pin that knocks out the old primer. The case on the right has already been resized.

Decapping means poking out the used primer from the cartridge case. A steel pin sticks out the bottom of most resizing dies. When you press the case into the die all the way, the pin pushes the spent primer out from the inside. You can buy a dedicated decapping die that does nothing but remove primers from virtually any type of case with a “boxer” (one-hole) primer pocket. There are reasons you may want to do that separately from resizing. We’ll get into that in a later article in this series.

Resizing straight wall pistol cartridges is easy. Most resizing dies have a carbide ring just inside the mouth. This steel is hard and slippery so the case won’t get stuck in the interior of the die. This is handy because you don’t need to lubricate these types of cases before resizing. Most straight wall case resizing dies also include a decapping pin, so the old primer is removed in the same step.

There is a second step to pistol case resizing we ought to mention here. A second case mouth belling die (or case mouth expansion die) opens the mouth every so slightly so there is room to insert a new bullet in the seating stage. The resizing die tends to close the mouth, so the case mouth expander opens up the lip just enough to allow a bullet to start the seating process. Less is better in this step as the bullet is held in place not by crimping, but by the case neck tension created during the seating step when the bullet is forced into the case. If you expand the mouth too much, the bullet will not be secure, not matter how much you crimp later. We’ll talk about this in detail in the “Seating and Crimping” article soon.

If you look carefully, you can see that the case on the right has a very slight expansion right at the mouth. It's already been through the case mouth expansion die.

If you look carefully, you can see that the case on the right has a very slight expansion right at the mouth. It’s already been through the case mouth expansion die.

Resizing bottleneck rifle cases like .30-06, .308 Winchester, or .223 Remington is a bit different.

First, due to the more complex shape of the resizing die, it’s hard and expensive to make a carbide insert. The bottom line? You need to lubricate your cases before resizing. If you don’t, the case will almost certainly get stuck inside of the die. And when I say “stuck” I really, really mean it. You’re not getting it out by tapping or with a pair of pliers. You’ll need to use a stuck case remover. That process involves drilling out and threading a hole in the stuck cartridge base, then using a bolt to slowly back it out. It’s almost like using a car jack, except your pulling the case out of the die with the “jack” as opposed to lifting something.

You need to lubricate bottleneck cases like these .308s before resizing. You can use a spray or roll them around on a grease pad like this.

You need to lubricate bottleneck cases like these .308s before resizing. You can use a spray or roll them around on a grease pad like this.

There are different ways to lubricate cases. If you use an oily spray or pad to distribute lubricant, then you’ll need to wipe that lubricant off after resizing. You don’t want oil getting inside the case where it can contaminate propellant. Also, brass cases and gun chambers are supposed to be dry. During the firing process, the brass expands and temporarily “sticks” to the inside of the chamber, thereby helping the bolt face keep the case in place while the bullet exits. Lubricant on the case tends to screw up this process. You can also use wax type lubes like Hornady One Shot. These aerosol sprays deliver a “drier” lubricant to the case while the carrier spray (alcohol or similar) evaporates. With these types of lubes, you have to wait until the cases dry before resizing. On the plus side, you don’t have to clean the lubricant off after. Do be patient. If you try to resize before the lube spray has dried, you’ll end up with a stuck case.

Another difference is that with most bottleneck rifle die sets, the case mouth is expanded by the resizing die. A “bell” on the decapping rod is pushed into the case body as the case is resized. As the case is withdrawn from the die, this bell is pulled back up through the case mouth, opening it back up to proper dimension.

I've removed the spindle on the Hornady .308 resizing die so you can see the decapping pin and the "ball" that opens up the case mouth as the case is pulled from the die.

I’ve removed the spindle on the Hornady .308 resizing die so you can see the decapping pin and the “ball” that opens up the case mouth as the case is pulled from the die.

For bottleneck rifle cartridges, you might hear of full length vs. neck resizing. That topic is too involved for now, so we’ll cover that in its own article at the end of the reloading process series. For now, know this. If you’re reloading ammo for use in multiple rifles or semi-automatic rifles, use a full-length resizing die. That shapes the entire cartridge. If you’re loading your own ammo, for use only in the same manual action rifle, you can resize the case neck only. From previous firings, the overall case will be sized perfectly for your chamber. Neck sizing only, when you can, might improve accuracy and increase the life of your brass.

Next up…

Next, we’ll get into case trimming. If you intend to reload bottleneck rifle of pistol cartridges, you’ll run into the need to trim your cases back to proper length after resizing. There are many ways to do this, and we’ll take a close look at several examples for both low and high-volume reloaders.

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