Wednesday, June 24, 2009

Reloading tip: Cracked nickel cases

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(click on the photo to enlarge)

There is some question about nickel cases and premature cracking from multiple reloading. Does it happen? A resounding.... Yes. Is it a real problem? Maybe.

The .45acp cases pictured above are of several brands, and all were found to be cracked during examination while reloading. They are in a batch of roughly 500 well used cased of about the same vintage, and have all seen roughly the same loadings.

While the nickel cases in this batch are showing cracking about five times as often as the plain brass cases, it might be worth noting the wear on the cases. This brass has been reloaded in excess of twenty times..... and owes the shooter nothing. As can be seen, it's been through the process so many times the nickel plating is actually wearing off the cases.

I take away two points from this situation:
  • I will not hesitate to reload nickel cases when I have them, and have no fears of 'short' case life with nickel.
  • I will examine nickel cases a little closer during reloading, and reserve them for mild target loads where a missed crack may not be such an issue.
Why use nickel plated cases at all, if they have even this small flaw? There are several good reasons. Chief among them (for me anyway) is that I pick them up at the range and they are free. Secondly, they resist corrosion when used in a carry/hunting pistol, and won't turn your leather gun gear a slimy green with age. Thirdly, they feed nicely in an auto-loader since the nickel plating is rather slick. Lastly, they clean up in the polisher in minutes, rather than hours.

Nickel plated bottle neck rifle ammunition is another story, and can cause reloaders to have fits. The hard nickel coating resists sizing to a point, and the higher pressures involved promote cracking at a much higher rate. They can also be a pain to trim, and are hard on the tool heads.

That said, nickel plated rifle cases are a fair choice for hunting, as they feed very smoothly and won't corrode under even the nastiest conditions. They'll have a shorter reload life than brass cases, depending on reloading method and pressure of the loads, but five or six loadings out of a single rifle cases are still possible.

For nickel plate pistol brass... the photo above speaks to that. Yes, nickel cases will crack more often, but not enough to shy away from using them. All it takes is a little more close examination as they age.

Commenter Sigivald asks a good question, and one I should have thought of myself. Exactly why do nickel plated cases tend to crack more often?

I think it has to do with the nature of nickel and brass, and their being dissimilar metals. They expand and contract at different rates, and react to sizing in different ways. One metal is trying to expand .005", while the other is attempting to go .008". The stress and strain put in place can pull metal apart.

I have read that the internal stresses inherent in the nickel plating itself leaves it stressed at 50% of it's fracture point even while sitting at rest. Add in repeated firing expansions, pressure, resizing, expanding, and crimping.... and something is going to happen. Brass is much more forgiving.

After photographing some nickel plated cases showing flaws (example above) I noticed that some cases have cracks in only the nickel plating... and not the underlying brass. This would imply flaws in the plating process, and delamination of the metals. I have to think such a crack in the plating would quickly lead to a case cracked completely through the body.



Tuesday, June 16, 2009

A range review of Brown Bear 7.62x39mm HP ammunition

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I recently had some time to spend on the range, and a friends Winchester .22 that needed to be sighted in. I'd been told that a local gun shop had a fair supply of 7.62x39, so I took along my vintage Chinese Type 56 just for fun.

The shop did indeed have a few cases of Brown Bear 7.62x39 hollow point ammunition, but at ruinous prices. $9 a box! I bought only two boxes, in the interest of a range report for my readers. Okay.... and because I wanted to play with the SKS a little.

The Brown Bear ammo, so named after the brown lacquer that coats it's steel case, is a product of the Barnaul munitions plant in Russia. Created by Aleksander 1st in 1869, the plant has supplied Russia, and now the world, with ammunition ever since
. Moved under wartime pressure several times, the plant settled in Barnaul and a month later was supplying Soviet forces through the rest of the war. First begun in St. Petersburg by Czar Aleksander as a royal ammunition plant, it's now adopted the name of it's home city and become the Barnaul ammunition company.

This new crop of Brown Bear ammunition comes in three choices. Full metal jacket, soft point meant for hunting, and hollow point meant for target shooting. It's interesting to note that Barnaul specifies the hollow point round as suitable for light game as well.

The case is steel, and coated with brown lacquer. The lacquer is thought by some to foul chambers with a sticky residue. In my shooting with the Russian import ammunition I have not noticed
this happening. Then again, I have fired only a few hundred rounds of the ammunition in a few rifles, and none in pistols.

The bullet appears to be gilded mild steel, with a lead core and a largish hollow point. The hollow point does not serve duty as a means to expansion, as the jacket is tough and not scored to tear back in petals. On impact, the Brown Bear hollow point is far more likely to fold over and destabilize the bullet dramatically. In match bullets like the Sierra boat tail hollow point, the precision hollow point helps balance the bullet and stabilize it in flight. Somehow, I doubt the Brown Bear hollow point is precise enough to have the same effect, but I did not notice this HP ammunition to be any less accurate than the FMJ either.

In shooting, the Chinese type 56 SKS functioned perfectly with the Brown Bear
offering. Feeding was slick, even flawless, and it shot to point of aim with the military sights on the rifle.

Accuracy was acceptable, although not stellar. The 123 grain hollow point bullets all fell into an average of 2.5" at fifty yards, with no fliers that couldn't be explained away
as the shooters fault.

Ejection was slightly erratic, with some cases flying forward, some to the rear, and
some straight overhead. This may have been more a function of the rifle, although it has ejected more consistently with other brands of ammunition. I can tell you one thing... it doesn't help accuracy testing to have a hot steel casing bounce off your skull a few times.

All in all.... the Brown Bear ammunition is exactly what it appears to be. Decent quality ammunition for everyday shooting and target practice. Match ammunition it's not, but it was not intended as such. Function is excellent, it's reliable, and accuracy is acceptable. Considering it's pretty much the only 7.62x39mm game in town just now... it's not too bad.





Thursday, June 11, 2009

Annealing case necks.... a simple and safe method

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(This blog is mostly about journaling my own adventures in learning. As I love my hobby with a passion, so do I love the learning process that comes with it. If someone else can profit in their enjoyment by my scribbling, then that’s icing on the cake. That’s what this article is about… a description of some of what I have learned regarding annealing brass case necks. As always, click on any images to enlarge them.)

So… what is annealing, and why bother with it?

Different metals react in different ways to stress and pressure. Steel, when heated to the correct temperature and cooled quickly (quenching) will grow harder. This is called heat treating. Reheating it to a certain temperature and letting it cool slowly will make it less brittle, and is called tempering. Aluminum does something different, as does lead, and so with brass.

Brass does not harden with temperature, but with ‘work’. As it is stretched, pressed, and sized it becomes harder, and more brittle. Simple age has a similar effect on brass. Taken too far in the process, brass will crack and fail. That’s what happens to cartridge case necks as they are reloaded multiple times. It’s especially prevalent with high power bottle neck rifle cases, and even more so with those getting heavily resized with each loading.

One of the features of brass is that it can be ‘annealed’, or softened with heat. Heated to a certain temperature, it becomes softer and less prone to cracking. The effects of many reloadings and firings can be negated with a single annealing process, allowing the cases to be reused far beyond their normal life span.

Annealing is also a pet technique of the long range precision bench rest shooters. These folks cringe or celebrate over a quarter inch group variation at five hundred yards. To them, annealing the case necks is a standard part of the hand loading process, as they aim at ‘precision nirvana’.

My reason for wishing to anneal case necks…. is that I’m too cheap to buy new brass. The Grand Old Turk I shoot in the rifle matches has a set of hand loads worked up on cases made in 1944. They were used when I got them, and I’ve since loaded them eight or ten times. They are starting to show their age! The last match I fired, I lost a case due to a cracked neck… and that means they are all ready to do the same. A new matched set of brass would cost me mo..mo..mo..money, and that is not acceptable if I can avoid it. Finding once fired and reloadable 8x57mm brass on the ground at the range… well… I won’t hold my breath waiting for that to happen.

Doing a Google search on ‘Annealing case necks’ will return thousands of hits, and at least a few of them will be scholarly works on the metallurgy of the process, and how to do it correctly. It’s not a mystery process, suited to hooded monks working in mystical caves. The only discussion that matters is in the process itself, with the real question being this: ‘How can it be done safely, uniformly, repeatedly, and for a reasonable price?’

There’s a dozen ways to do it, and many of them are workable. Some are downright dangerous, and one or two are impressively high tech (and expensive). This article is about the method I worked out for myself, being a compromise to reach my simple goal. I’ve borrowed points and ideas from several sources, putting them together into an easy process that appears effective, safe, and inexpensive.

The temperatures used are critical, for several reasons. Foremost among them is safety, as the lower body and base of the cartridge case must never be annealed and soft. If it’s heated above 480 degrees or so, the grain structure of the metal will change and the case may not be able to contain the pressure of firing (think face full of flaming debris). On the other hand, the case neck must be heated to about 750 degrees for some seconds for the annealing process to take place. Doing one without doing the other is the real trick.

The next problem is actually judging the temperature correctly. Some folks swear by working in a darkened room and judging temperature by the color change of the case. In other words, they watch it turn dull red under the flame, and then quench to stop the heat spreading. The problem with this method is one of judgment and timing. The line between ‘dull red’ and ‘turning orange’ is only a few degrees and a few moments in time. Over-annealing the case will make it too soft, and ruin it.

I found and use a ‘Tempilstik’ to judge temperature. This is a chalky crayon type of marker used by welders and metal workers. Rubbed on the metal to leave a mark, the material will melt at a relatively exact temperature. It costs about $11.00 at most welding supply stores, and is usually in stock. They come in varying temperature ratings, and I chose 650 degrees for this use.

I found it’s best to work with dirty, as-fired cases. Brass cases freshly cleaned are very hard to mark with the chalky Tempilstik, and the cases need to be cleaned and sized after annealing in any case.

Using the temperature sensitive marker, draw a line of the material around each case about ¼” below the shoulder. During heat treating the neck, the heat will soak through the brass to the body, melting the marker when it reaches 650 degrees at that spot. The neck will be hotter, and should be in the correct range for annealing. It takes six to eight seconds for the heat to soak that far, and that’s long enough for the annealing process to happen. I found that even a faint line of Tempilstik is visible while the case is spinning, and not much is required. The state change from solid to liquid of the indicator marker is readily visible under good lighting.

The cases are slowly spun in the flame using a battery powered drill/driver with a low speed setting. As a case holder, I used a 1/4” drive shallow 1/2” socket, with a 1/4” bolt inserted through the square drive hole and a nut tightened in place. The shaft of the short bolt that protrudes can be chucked into the drill/driver snugly. Spinning the case within the flame makes for an even annealing process, and is the biggest reason I opted away from the ‘pan of water’ method.

The process works like this:

Have a propane torch standing on the bench. It works best if the short and squat cylinder is used, giving the torch a wide base to stand on. Have the torch running full blast, with the flame pointed away from you (and NOT at flammable objects!).

Have a small pan of water on the bench just in front of the torch, placed so the case can be tipped into it from the holder once proper temperature is reached.

Have the case holder chucked in the drill/driver, and the tool set on its low speed ‘driver’ setting. Begin spinning the case before it’s moved into the flame.

With the case spinning, move the neck into the flame until it’s fully enveloped. Make sure the flame is pointed from the base of the case to the mouth, and the flame washes away from the body of the case. Do not have the flame wash over the Tempilstik marking as it will melt at once, no matter the actual temperature of the brass case.

With the case spinning, and the neck enveloped in the propane torch flame, watch the temperature indicating marker. Once it melts, tip the holder forward and dump the case into the water.

That’s it. The case is now ready to be sized, polished, trimmed, and reloaded.

It’s advisable to practice the process on scrap cases until the timing and rhythm is learned. I went through half a dozen junk 30-06 cases as I learned how to hold the case in relation to the flame and for how long. Once this is worked out, repeatability is good and a large batch of cases can be done quite quickly. It takes longer to scratch on the marker than the actual annealing process takes.

Annealing case necks is not something that needs to be done often, unless extreme precision is the desired outcome. For rifle cases that are to be loaded more than a few times, it’s a good technique to use. If the shooter is forming cases through a multi-step die process, annealing the necks is a must-do step. For ancient brass, unusual calibers, or perhaps for those of us just too cheap to buy new cases…. annealing can save the day.

Tuesday, June 9, 2009

New on the sidebar: Images from the military rifle matches


On the side bar, an image that links to a slide show. It's comprised of photos from the SLCFSA military rifle matches, and will grow on occasion as more images are uploaded to the show.

I shot in the D-day match with the 1938 Turk this past weekend and scored a respectable 346/500. My son whooped my butt, using one of my rifles, and beat me by 20 points. Brat. The boy can shoot.... thats for sure.

During a lull, I was talking with another shooter about annealing cases. It turned out he is (a) a materials engineer, (b) a long range precision shooter, and (c) a very serious person with his hobby. He's done studies on annealing brass, including sectioning cases, etching, and crystalline structure analysis. He told me of a simple way to anneal my case necks that works, and I'll be trying it soon. Naturally I'll write it up for all to share. Look for it in the future.

Monday, June 8, 2009

Range time with an old Mauser, the Yugoslavian M48B

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It's a good day for Range time with an old battle rifle, all the better to remember the sacrifices made by our soldiers over sixty years ago on far away beaches. This weekend saw endless articles on the D-day invasion, and many commemorations of the event. Happening before my time, the stories my father told still ring clear out of memory.

On this day, I'm shooting a Yugoslavian M48b Mauser in pristine condition. I discussed this rifle, and it's brethren some time ago on this blog. No, it never saw a beach, nor even a battle, but it shares in the Mauser heritage, which saw fighting in every war of the 20th century. Different people remember and commemorate in different ways. I choose to spend some range time behind a rifle, and give thought to what those men faced so long ago.

I placed a few targets at 100 yards, and three at 200 yards. Now, some
readers might be saying things like: "Right, two hundred yards with an old Mauser and open sights!" Or, maybe something like: "Good luck you old fart, I hope you were able to hit the hill!"

You see, the sights on this Mauser (made in the '50s) are basic
ally the same as they were on those made in the late 1800's. A tiny V notch rear and an inverted V front blade. Small, hard to see, and difficult to align. In addition, the trigger is rough two stage military, with a long raspy take up and a crunchy let off. Could these things be 'fixed'? Yes, easily..... and I have done so to other Mausers that are not so matching and perfect as this one.

No, this particular rifle will be kept as found, and fired as such.

But.... It was built as a battle rifle and it shoots like one, with all the good and bad traits that entails. In this case, it means shooting into a one foot target at 200 yards is not so difficult. Just shoot the rifle as it was built to be used!

Now that doesn't mean 200 yards looks any closer. As the photo shows.... those targets get small when they are way out there! Yet.... nothing ventured, nothing gained. Lets take the shots and see what happens.


video

Having fired my five at 200, and wanting to see the damage close up, I revved up the mobile footwear and trekked the length of the range. Truth be told.... the bench looks as far away from the targets, as the targets from the bench. Who woulda thunk it?

Hmm.... five rounds, five holes. Not bad for an old battle rifle firing ammunition equally as old, especially with eyesight like mine.
A little more reality... the target shown below was the best of the three... The old eyes really do need a little help now. I'll shoot open sights as long as I can get away with it, but I have no qualms using good optics when precision is key.

The rifle was designed to be fired standing up. Used that way, it's not hard to handle, and launches the 196 grain bullets down range with minimal damage to the shooters shoulder. If I was shooting a 58 round match with this rifle, it would have a temporary pad installed, but for just plinking at some targets the recoil is part of the charm.

That said, bench shooting is a different story. Here the rifle sits differently and the body can not absorb the recoil as easily. Far more is transfered directly rearwards to the shoulder. This can seen in the slow motion video of a round being fired from the bench...


video

My suggestion.... install a temporary strap on pad if bench shooting more than a few rounds with a short Mauser like this! I can shoot a double match with my long Turk Mauser, over 100 rounds, and not mind a bit. Ten from the bench with this shorter rifle has more effect, and not as pleasant.

Today I was shooting 1950's Yugoslavian surplus military 8x57
ammunition. Very corrosive.... so good cleaning is a must. I began the process right there at the range, with a thorough swab out using Breakfree CLP. Cleaning right away lessens any chance of forgetting, or of damaging the bore from corrosion. I shoot a LOT of old surplus corrosive ammunition, and simply cleaning quickly and well is all it takes.... just a few minutes extra.


Clean early, clean often, and shoot more often too! Life is too short to pass up on the enjoyment of it.




Saturday, June 6, 2009

Reloading tip: Avoiding the dreaded double charge


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I don't believe modern powder measures that are properly used and cared for will throw wildly varying charges. Perfect charges every time? Regretfully, probably not. Charges with differences of a grain or two? I tend to doubt it. Having used mechanical powder measures from the utilitarian Lee powder scoop, up to excellent quality bench mounted precision micrometer equipped measures, I think every single one is quite capable of tossing a nearly perfect charge each time if used properly.

Still, we shooters hear stories of the dreaded 'double charge' that has dissembled a pistol (or rifle) in a dramatic and unfriendly way.

Does it actually happen? Yes, I think it does. While I suspect the lore might also include hand loaders who made serious mistakes with p
owder selection and handling, loading the wrong powder to the wrong charge, there is possible such a creature as the 'double charge'. It's cause, almost surely a distracted hand loader or poor procedures.

My cure is simple. No distractions, period. I don't reload with friends around usually, and if I do they are hand loaders as well and know when to shut up. In addition, very bright lighting over the bench, and a few simple procedures designed to catch a double charge.


On the rare occasions I use my RCBS Ammomaster progressive press, I have a spot light aimed exactly where it will shine down into the charged case. I glance at every single case before I place a bullet into it. Anything with a funny load gets pulled out of sequence, and investigated. I've never found a double charge doing this, but I see no reason not to be careful.


Loading single stage, as I usually do, I throw all my charges as a set. Then, under the bright lights of the loading bench, I take a moment to carefully examine the charged cases. As the image above shows, a double charged case stands out like a sore thumb. This mornings loading included 9x19 practice ammunition with a light charge of fast powder. A double charge would have easily accepted a seated bullet, but would also have exceeded maximum charge with that powder.

Bright lighting, no distractions, and at least one dedicated examination of the charged cases. Simple measures to eliminate a very real danger.

Thursday, June 4, 2009

Reloading tip: Beware the powder measure knocker!

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The old Lyman Ideal powder measures from the early 1900's had a neat little widget on them. It was nothing more than a tiny metal bar, or hammer, hinged on the side of the powder measure. In use, the reloader raised the bar once, allowed it to fall and hit the measure a sharp rap, and then he threw his charge. The mild impact and vibration settled the powder in the measure, giving a more compact and consistent charge. The old timers knew what they were doing, as even to this day good reloaders know to be consistent with operating the handle when they throw a charge.

It's this ability of most powders to settle with vibration that can cause a problem. If,
like many reloaders, your powder measure is mounted to the bench along with the press, then each throw of the press handle can act as a 'powder knocker', settling the charge in the measure. This throws a random action into the job of measuring the powder charge, and inconsistent charges can play havoc with accurate ammunition.

If the measure is set to throw a maximum charge for a load, or is stocked with a very fast powder such as Bullseye, then the extra powder compaction can cause the thrown charge to be over the limit.

It's good practice to throw every charge of a set one after another, and then seat bullets in the case. The first few powder throws should be made into a clean container and dumped back into the reservoir. Never to be forgotten... check the occasional powder charge on a good quality scale to ascertain the measure is doing a consistent job and the settings have not drifted.

If the powder measure is left stocked with powder for some reason, it's always wise to begin the next loading session by throwing a few charges to be dumped back in.
My personal practice is to do so, but refrain from dumping the last sample thrown into the reservoir until after I am done charging the case set. I think even the act of pouring in a few grains of powder can settle the powder column, even if only a little.

Careful consistency is key!