Reloading Accurate Rifle Ammo – Part 1 – Case Preparation

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Zeliard
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Reloading Accurate Rifle Ammo – Part 1 – Case Preparation

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Originally posted by Carteach0.

Note: This information was originally posted in 8 different posts. I've combined them into fewer, but related, posts.

Reloading Accurate Rifle Ammo – Part 1 – Case Preparation


Case Prep, Part 1

Hand loaders have so many choices. They can chose to do the minimal amount of work
needed to arrive at blasting ammunition, or they can take extreme care in loading match
level precision works of art. In either case there will be some level of case prep involved.
This series of articles will focus on various techniques of case preparation for hand
loaders.

Hand loaders are particular people, and many are quite opinionated. It seems to go
with the breed! While I am presenting methods that I chose to use, I am sure others
can and will chime in with their own special techniques. Listen very carefully, then
decide what makes the most sense for you. There is seldom a path of failure involved
when following the published directions in major reloading manuals, and I personally
recommend giving them serious consideration.

This series will follow as some cases are prepped to join their brothers as a set to be used
for Hi Power match shooting. In this case, 8x57mm to be fired in the Grand Old Turk
model 38 shot regularly in the matches. This rifle shoots decently with Mil-Surp
ammunition, but responds spectacularly to carefully hand loaded ammunition matched
to the rifle.

Some 50 cases have already been prepped by the methods presented, and another 50 or so
will be done here. That should give a little over 100 matched cases. That’s enough to
shoot a match and practice as well.

Here is an example of the end product we are attempting to reach:

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It might be a surprise to find out these are military cases made in 1944! Despite their age
they are fine shooters with the load built for this rifle.

The realm of the hand loader is ripe with gadgets. Tools to do this, tools to do that,
and certainly tools to do some other things as well. In each case, the best value
seems to be in quality tools, but money can be saved with some common sense choices
and adaptations. This idea will be no strange idea to Mil-Surp shooters.

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A simple tool that is indispensable will be a ‘loading block’. This is nothing more than
a wood or plastic tray with holes to stand cases in. I own both, in many forms. The
simplest (and my favorite) is a set of hardwood blocks. Frankly, nothing more fancy
than a chunk of 2”x12”x12” pine board with fifty .5” holes drilled one inch deep will
work fine.

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I chose to, and believe it makes sense to, clean my cases for a short time before going
forward with the preparation process. These cases are going to be sized in precision
dies, and must be carefully examined. In both instances clean cases work better.
Clean brass will also cause less wear in our expensive dies.

The generic vibratory polisher does a fine job, although there are countless
ways to clean brass. Tumblers, liquid baths, dishwashers, clothes washing machines.....
Hand loaders tend to be resourceful people when it comes to their hobby!

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The polisher on the right is running with a load of crushed walnut and about one hundred
rifle cases. To my plain crushed walnut I add a few tablespoons of ‘Rain Dance’ liquid
car wax as a cleaning and polishing agent. Other commercial polishing medias are available, but I find the simple crushed walnut sold as lizard bedding in pet stores
does a great job at half the cost of name brand polishing media.

The polisher on the left..... well...... that one is set up with fine steel shot and
powdered graphite, and I use it to impregnate bullets with a graphite coating.
As said...... hand loaders tend to be inventive tinkerers.

While there are some really neat looking case/media separators sold by reloading
suppliers, once again I chose another road. In this case a simple two dollar plastic
strainer does a great job. Shaken out over a two dollar plastic dish pan, it does the
job in minutes with little stress, and makes fun jingling sounds too!

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Once cleaned a short time, in this case about thirty minutes, we have a nice pile
of brass to work with.

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The first step of our preparation process is to size the cases. If they have been fired in the
intended rifle already, then simple neck sizing might be the choice. Since these fired cases were not shot in my rifle, they needed to be full length sized. Not just the necks, but
the bodies of the case as well. This calls for a full length sizing die set, and as always
quality can’t be skipped in some places. Loading dies is one of those.

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RCBS makes products generally accepted as top of the line. Their quality is usually
exceptional and their warranty is beyond reproach.

Now, to full length size brass cases, they must be lubricated. Failing to do so will
cause need for another fun tool known as the ‘stuck case remover’. I will confess I own
one of these and have had to use it many times. I’m not proud of that, but it speaks
volumes that RCBS knows reloading and reloaders so well that they make this product
and carry it in their line.

When it comes to case lubes, I have at least four pads and five different kinds of special lube. Do you think I would use any of these? Of COURSE not! Instead I act from
shear laziness and cheapness, using a ‘special’ lube procured from the special reloading
suppliers handily located within my local grocery store.

I use a spray cooking oil...............

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Just a few spritzes will do nicely, and a new user will surely spray too much. Just a dab
will do, swirling the cases around a bit to spread the oil. Too much lube will cause issues
and possible case damage, not enough causing stuck cases. Just a tiny bit........ that’s it!

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Since full length sizing was the goal, the die was screwed right down till it nearly touched
the shell holder. This insured the cases will chamber without too much trouble in the
tight chamber of the Grand Old Turk mauser.

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The result, as illustrated by the case on the top of this photo, is a neck sized about
90% and a base sized only as much as needed without overworking the brass.

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As the cases are sized, they are dropped back into the strainer for another easy but
necessary step. The excess oil must be wiped from the cases. Once again, laziness
provides an easy way to do this job. A clean rag swished around and through the cases
gets the bulk of the spare oil off the cases, and ready for the next step.

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Now that the cases are sized and wiped down, they must be examined. Each case is held
under strong light while searching for any flaw at all. Deformed cases, bad necks,
incipient cracks, set back shoulders, corrosion, rim issues, off center flash holes, etc.
As each case is passed through examination, it can now be racked in the loading block.
Make a habit of using the block as a tool to control processes, moving cases from one
side of the block to the other as each step is performed.

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The sized cases are now ready for their final polish before moving on with the case prep.
While there is much left to be done, none involves lube and of course hands will be clean
each step of the way. That being the situation, back to the polisher they go!

My habit is to let the polisher run overnight on a final polish with cases I really
care about. Again, they are jingled around the strainer to separate the media, then
racked back into the loading block. Shiny brass is a lovely sight!

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Some reloaders would stop their case prep right here. Once all the additional steps
are done, stopping here in case prep is not a bad thing. On the other hand,
the steps to follow are important to accuracy and I seldom pass on them unless the
cases have already been fully prepped. Many of these steps are only done once to
the case, or seldom done, so the extra time taken here is an investment in accuracy
that almost always pays off in a big way.

What follows? LOTS! Tune in again for the good stuff...........................…

Case Prep, Part 2

In part one we reviewed some basic case preparation work with 8x57mm fired cases.
The article left us with a basket full of nice shiny sized brass, all ready to proceed.

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Our next logical step, and one that’s required for accuracy in every case, and safety in
some, is to trim the cases to proper length. I have found that, while having the case
length set close to spec is important, having a matched set of brass with *matching*
case length far more important. If each case neck is the same length, and bullets are
seated to the same depth, then neck grip on each bullet should be the same. That means
each round will have a better chance of leaving the case in the same way, and each
round will have a better chance at equal chamber pressure and powder burn rate.

Important? Yup, you better believe it!

There are many way to trim cases to length. Simple to complicated, both hand and
powered are available. I have tried many of the usual methods and a few unusual ones,
but years ago settled on a plain Jane Hornady hand operated unit.

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It comes with a large number of pilots that center the case mouth against the cutter head
and uses standard shell holders to grip the case. I mounted mine to a small board which
can be clamped to the loading bench, or carried out to the back deck. There the sun
shines, adult beverages are easily at hand, and Momma is happy to have me around.
If confession is in order..... I have even trimmed cases while watching TV.

In use, with the proper pilot in place, a case is mounted in the trimmer and carefully trimmed a bit at a time till it’s the desired length.

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That leads us to a question that must be answered. Exactly how long should the case be?
That varies considerably. I’ll relate how I make my choice, but every hand loader has
to decide on their own what’s best. In my case, since accuracy is a strong goal and I
know every case must match to achieve this goal, I measure all the cases till I find the
shortest one. If one or two are far shorter, they are tossed in the ‘spare’ pile.

The shortest one is then mounted in the trimmer and the case mouth is just squared off.
That case becomes the set up gauge for the trimmer, and every other case in this group
will be trimmed to this same length.

There are many kinds of trimmers available, but be careful and give the choice some
thought. One of the cheaper trimmers uses a long pilot that actually references the
cut to the inside of the case at the primer flash hole. There is a danger in that course.
Not every case is exactly the same at that point, as we’ll see later, and using
that point as a reference means uneven case lengths.

Once all the cases are trimmed, we’ll need to chamfer the case mouths. The trimming
process will leave the case mouths with a flashing both inside and out.

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Once again, there are many tools and gadgets out there for this. On smaller cases I
have used a screwdriver, and old timers often swear by a sharp jack knife.
Myself, I mostly swear *at* sharp jack knifes and prefer to use a Wilson
case chamfering tool.

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This simple and inexpensive tool does an excellent job. It cuts quickly
and with good control. A few twists of the case and tool will cut the flashing
off and leave the case mouth with a smooth bevel that won’t snag while feeding
or shave the bullet on seating.

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Now that the case has been trimmed to length and the mouth chamfering done correctly,
it’s time to clean up the inside of the case neck. Once again... this job is a snap.
If there are only a few cases involved, a few twists with a case neck brush does
a fine job.

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If there are more than a few cases, a decent cleaning brush chucked in a cordless drill
will do a hundred cases in about four minutes flat. Just a short BZzzzzzz in each case
mouth is all that’s needed.

Is this step required? Well....... I think so. Grab a flashlight and take a close look
at the inside of the case neck. Now, clean it well and look again. Which
case neck will do a better job of releasing the bullet in a regular manner?

At this stage of the case preparation process, I usually stop and clean my tools and
work area. Good quality tools are worth buying, and certainly worth
taking care of.

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So.... to recap......

We gave the cases a brief clean up, then lubed them. The cases were then full length
sized, wiped down, and examined. Then they went back to the polisher for long enough
to become jewel like sparkling bits of joy. After this the cases were trimmed to length
and the case necks were chamfered smooth. Then the inside case necks were well cleaned.

Still with us? Good...... lets move on!

What? You thought we were done and ready to load?

BWAHAhahahahahaha.......... Not by a long shot!

In part three we’ll look at the other end of the case. The primer pocket needs some
care, and usually a small redesign job. The flash hole will also get some one-on-one
counseling to repair leftover manufacturing flaws.

Stay tuned friends and neighbors..... there is more good stuff coming!

Case Prep, Part 3

In parts one and two, we took a batch of 8x57mm fired cases and completed much of the
work involved in preparing them for loading. In this third and final article we’ll examine
some methods of dealing with primer pocket and flash hole issues.

The primer lights the fire on a rifle cartridge, and lighting that fire the same way every
time contributes to highly accurate ammunition. Buying quality primers is a good start,
but giving them a good home counts too.

Let’s look at the primer pocket on an once fired military case:

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Well........ Yuck! It’s dirty, misshapen, rough, and generally unloved.

As a military case, it has the usual primer crimp. This is placed to keep the primer
inside the pocket during rough firing and handling. A primer falling out could
tie up a machine gun during battle, and that would be bad. To the military that’s important,
but they don’t reload. To a handloader, that crimp has to go.

There are two accepted ways to get rid of this nasty old crimp. We can ream it off,
or iron it out. Cut it or swage it.

As usual, I can’t leave well enough alone and chose to do both.

To start with, swaging the pocket makes sense. Case prep usually involves removing
material, and we need that material on the case, not the bench. The primer crimp
originally came from the case, so if we can press it back where it belongs, great!

I chose to use a RCBS primer pocket swaging set.

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Since this is a once and done operation, the extra time involved is not really a big
investment. The RCBS tool has an easy setup and is very positive in operation. It
works well...... and that’s enough.

In use, we slip the proper anvil into the press ram and the case
guide into the press head.

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We can either set the deprimed brass onto the anvil, then press into the case guide, or slip
the case into the guide and run the anvil into it. I’ve done both, and it really depends on
the way the case fits. Care must be taken not to crush the case in any way, as most
presses have enough leverage to mangle a brass cartridge.

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Once run through this process, the crimp will be mostly ironed back into the case and
technically we could go ahead with loading the case.

Technically................ we could. Is that good enough?

Nawww..................

The press process will leave a small lip on the primer pocket. I find this makes
primer seating problematic at times. Why put up with it when there’s a gadget
to deal with it?

Lyman has a primer pocket reamer that’s shaped just right to give us a nice shoulder
on the pocket. In use, just twist it into the pocket and spin gently a few revolutions.

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Ok, are we done with the primer pocket? Again, no way....

The primer seats against the base of the primer pocket. Bench rest shooters have
understood for generations that a squared off and uniform pocket means a uniform
primer ignition. This means another tool, and here quality is everything.
We are talking about a precision cutting tool.

While I own several, the single best I have ever seen is the Sinclair primer
pocket uniformer. It fully adjustable and the cutting bit is razer sharp and perfectly
formed.

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Once the other primer pocket operations are performed, spin the uniformer into the
pocket, removing it every few spins to clear the chips. Having done this properly,
the primer pocket will look amazingly different. It should now be almost perfectly
even and sharply machined.

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This is another of those once and done operations. Avoid using the uniformer as a primer
pocket cleaner. It will work fine, but eventually will dull the cutting bits.

Are we done yet? Are we done yet? Can we load them yet? Are we done YET??

NO! Put your powder away and sit down.

We just dealt with the primer pocket where the fire starts, but how does that fire
get into the case? The flash hole of course! What could possibly go wrong
with a hole in the case? I’m afraid there’s a lot that can be wrong.

The flash hole is not drilled into the case, but punched. That means a rod
is just rammed through the base of the case and a port is roughly punched
into the metal. That almost always leaves a flashing, or other issue with
the flash hole. If the hole is not even and precise, then the fire issuing into the
powder charge will not be even. Since we are in search of precision accurate
ammunition, this problem must be dealt with.

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I chose to use an RCBS flash hole tool that introduces a small reaming cutter
bit into flash hole inside the case. It’s guided by a precision pilot matching the
caliber of the cartridge. The depth and precision of the cut is based on the guides
fit into the case neck. This is one reason why the cases *must* be trimmed to length
before performing this operation on the flash hole.

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The first case is done as a set up operation. Leave the pilot loose and make some gentle twisting cuts
into the flash hole. The flashing can be felt as it’s cut away, and just a spin or two after the
flashing is removed the hole will be clean with a nice light bevel. The flashing and debris
must be dumped from the case afterwards. Looking into the case with a bright light should reveal
a flash hole with a brilliant tiny brass ring around it.

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My friends.... we have now arrived at the point where our cases are ready to load.

Could we do more? Of course we could. There are bench rest shooters who would spend
this much time solely on their case necks, machining each to a thickness variation of
.0001”, and polishing it perfectly. That said, understand that the benchrest
shooter usually has a rifle that responds to such precision, and that shooter is searching
for group sizes little more than one bullet diameter wide at 100 yards.

For military and commercial rifles, more case prep than these three article cover
is probably an exercise in diminishing returns. I’ve seen average commercial
brand name rifles shooting groups less than .5 inches with cases prepped exactly
as described here, consistently.

Could we do more? Yup.... and go ahead if you wish.

As for me.... I’m ready to load up and go shooting!

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Proud alumni of Transylvanian Polygnostic University. "Know enough to be afraid."

"Vertroue in God en die Mauser".-Faith in God and the Mauser.

"Send lawyers, guns and money." -Warren Zevon

yooper_sjd
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Re: Reloading Accurate Rifle Ammo – Part 1 – Case Preparation

Post by yooper_sjd »

doing my berdan conversions, I improvised a few of these tool. Correct with flash hole uniformity! but with my berdan conversions, I got three flash holes regardless. I get a pretty quick ignition....

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