One of the issues I have had is that my brass continues to disappear at the range. I’ve had some luck getting range brass from friends, but not nearly as much as I want.

My last “big” score was 125 pieces of 8mmx57 Mauser for “only” $75.00. Of course, that was my frequent flyer discount along with the fact that it was part of “discount the brass, or I’m not going to buy this here $1000 rifle”.

I was pleased with my last reloading session and wanted to finish filling my ammo cans with 5.56×45. Somebody mentioned Diamond K Brass, so I went looking.

Their prices were so low that I was concerned they might be a scam. They most certainly are not.

When I buy brass from the standard places, if they tell me they are sending me 100 pieces of brass, I’m going to get 100 pieces of brass. Maybe I’ll get 101 pieces.

I took the plunge and ordered 1000+ of .223/5.56 from Diamond K. There was shipping, I was about to walk away when I did the math and decided it was acceptable at $22.00 for insured to me.

What arrived was a boat load of brass. The brass was cleaned but no deprimed. That was my first step.

There was a mix of head stamps. The mix seemed to be about 50/50 .223 and 5.56.

Of the 1000+ cases, I had 4 cases that were too damaged to use. I might have been able to rescue 2 of them, as it was just the case mouth. With a bit of time with the proper tool, I could have opened up the mouth enough for the sizing die to correct any remaining damage.

There was one .300 blackout case. There was one .22LR case. There were two cases that had no powder, but the bullet was still inside the case.

My biggest issue was that one of the head stamps has a primer flash hole that is too small. I can’t get my decapping pin to fit through to punch out the primer. I destroyed one decapping pin when I pushed too hard.

I have a tool on order to bring the flash holes to the correct nominal size. That will happen this weekend. At which time I will be able to finish decapping the cases.

Was the price right? YES. This is good-looking brass. I will be placing more orders with them shortly. Looking at 2000+ .45 ACP, 2000+ 9mm, more .223/5.56, and maybe some strange brass as well.

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When a cartridge is fired, the powder burning creates high pressures. 9MM has a maximum average pressure of 35,000psi. A 7.62×51 NATO has a maximum pressure of 60,200psi. These pressures are high enough to move metal.

1/16″ to 3/5″ brass pipe fittings and standard nipples can be used up to 300psi. In certain applications, the pressure can go to 1000PSI, maybe.

What this means is that if the cartridge case is not supported, it will burst under nominal pressures. This process of the case expanding is a “good thing”. It acts to obturate the flow of gasses around the case and out the breach.

For a cartridge to fit into the supporting chamber, it must be slightly smaller, in all dimensions, than the chamber. If it was an exact match, the round would be difficult to chamber.

When the round is fired, it “fire forms” the case to match the chamber. When the pressure goes down, the metal moves back towards its original size, slightly. This allows it to be extracted from the chamber, more easily.

To help with the extraction process, cases are often designed with a slight taper. When the cases are extracted, as soon as they move back even a small amount, they lose contact with the chamber walls.

When we speak of “straight walled” cases, we typically include these slightly tapered cases.

When the size of the diameter of the bullet is significantly less than the diameter of the case, the case needs to be “necked down”. This creates a “bottleneck cartridge”.

A bottleneck cartridge has pressure pushing the brass forward when the round is fired. This causes the case to stretch a little.

Headspacing

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This is a LibreCalc document. You should be able to import it into Google Spreadsheets as well.

Cartridge Cost

Case preparation starts with getting some brass. In my situation, that is range brass. This is brass that I’ve picked up off the ground at my test range or the shooting range. The only thing I know about this brass at this point is that it is brass and not aluminum or steel.

Notice the green sealer around the primer of the top 5.56×45 case. This indicates that this was likely a military specification round. That sealer is designed to keep water out. The primer is also “crimped” or “staked” in place.
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The simplest press is a single stage press.

When starting with range brass, selected for the caliber you wish to reload, you start with an inspection. Then you deprime/decap the case.

You select the correct shell holder for your cases. For 5.56×45 it is a #4 shell holder. This is installed at the top of the ram with gentle pressure.

A decapping die is placed in the top plate and adjusted properly. When you bring the lever down, the ram goes up. The decapping pin then slides through the flash hole, and the pin then presses the primer out of its pocket.

When you raise the lever, the ram goes down and you can remove the case.

You repeat this process for each case you have to process.
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I’ll be addressing comments from Part 1 at the end of this article.

To make a cartridge, you need to place a primer in the case, then add powder to the case, and finally place a bullet in the mouth of the case.

The thing that starts your freedom downrange is the spark button/primer doing its job.

In order for it to do its job, it must be the right type and the right size.

We’ll talk about Boxer primers first.

Both of those cases are 7.62×51 NATO rounds. The top case uses a Berdan primer. The lower case uses a Boxer Primer.

Boxer primers come in two diameters, large and small. They come in three sensitivities, pistol, rifle, and military.

So what are the dimensions of these primers?
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