A question I’m often asked by those new to new handloading is: how may times can I re-use a cartridge case? Since its cost is the major item in reloading cartridges, the question is one that newchum handloaders spend a lot of time worrying about.
It’s not an easy question to answer because there are a lot of factors involved. For instance, a load that seems perfectly normal in a good case will show many signs of exceesive pressure in a poor one. A poor case subjected to an average pressure of only 45,000 psi may have to be discarded after two or three reloads, whereas a good one may last for 20 or 30 loadings with pressures of 50,000 psi. In other words, a case of tough, springy brass – neither soft nor brittle – can be reloaded far oftener than one of poor quality.
A case that’s too soft soon gives rise to extraction and seating trouble, because the brass does not relax its grip and spring back from the chamber walls when the pressure goes down. Primer pockets in the soft case quickly enlarge and leak. The case is then useless and should be junked at once.
Cases that are too brittle soon develop neck cracks, and I’ve seen cases split not only the necks but halfway down the shoulder on the first firing. If they are full-length-resized they may crack toward the head. I have seen extremely hard, brittle cases crack across the head at the first firing.
Full-length-rezizing is particularly bad for a case that’s been fired in a sloppy chamber (one that’s badly oversized). Working the brass at the point of maximum expansion, near the head, makes it brittle – just as bending and working a piece of wire will cause it to break. When reloading cases for a rifle which has a badly oversized chamber, it is wise to full-length- resize cases only once; then when they become difficult to seat and extract, dump them in the garbage.
That’s the cautious and sensible thing to do. But when a case is fired in a chamber that is a snug fit at the rear end, there is very little expansion, and then the case may be safely full-length-resized many times. Thankfully, in this day and age, batches of poor brass don’t turn up as frequently as they used to a few decades ago, but it still happens on rare occasions.
There’s a school of thought that holds to the idea that you shouldn’t full-length-resize cases every time you reload them. They claim that this is a sure way to ruin good brass in a short time, and that they’ll soon develop cracks around the case at the point of maximum expansion, just in front of the solid head, resulting in a partial or complete head separation. They recommend that instead you should merely neck-size cases, and only resort to full-length-resizing when your reloads won’t chamber easily.
That’s a pious idea, one what I would surely endorse, but only if we are sure we have good quality cases. Happily, most modern brass is tough and springy and I’ve found that full- length-sizing every time you reload, has no deleterious effect upon case life. In some instances a handloader thinks his rifle has developed excessive headspace, whereas the most likely cause is either overworked brass or poor adjustment of the full-length die.
Rimless cases can be quickly ruined by light loads. The blow of the firing pin drives the whole case forward, lengthening the neck and shortening the body before powder gas can expand the case against the chamber walls, which it would do with a normal full power load.
When a light load is used the primer frequently drives back against the bolt face. Examination then shows that the primer is protruding. The case has been ruined. Next
time it is fired it will produce greatly excessive headspace and may suffer a complete head separation. That’s one reason why I’m not wildly enthusiastic about using those light loads that make a .32-20 out of a .30-06. If you are going to use squib loads, then play it safe and keep a box or two of brass for that sole purpose. Don’t take chance by loading full power loads in cases that have already been used for squib loads.
Working pressure has a lot to do with case life. Good cases used in properly dimensioned chambers at pressures from 40,000 to 45,000 psi will last practically forever. One hundred .222 Remington cases I bought in 1990 have been used with moderate pressures and every one has been reloaded at least 20 times. Most are still in good condition.
Every time a cartridge is fired, the case neck expands to let go of the bullet. It then has to be sized down and re- expanded to the proper size to hold a new bullet. With each firing brass moves forward and the neck lengthens, so it will need trimming back to normal length after every third or fourth shot. But some cases which have a long tapered body stretch more than others and may need trimming after every reload.
The brass also grows brittle. Usually a good case has reached its use-by date when a neck crack appears, but I have seen some necks get so thin, that although uncracked, they’d no longer hold a bullet. Annealing is sometimes recommended as a cure for brittle necks, but it’s time a consuming process and seldom worthwhile. Better to junk that lot of brass
and buy a new batch.
Cases subjected to high pressures eventually develop loose primer pockets. So when you can seat a primer with only a little pressure, its time to discard the case.
Anyone who does much reloading discovers that brass cases vary a lot. Some are way too soft and almost worthless for reloading. Some are so good that they’re worth twice what you paid for them. So, to sum up, the life of a case depends on how good it is the first place, what sort of chamber it’s fired in, the degree of pressure it’s subjected to, and how well you look after them.
Warning On OverloadingEvery now and then a handloader manages to blow up a rifle or reputable make with one of his own reloads. But he seldom wants to accept responsibilty for this and tries to offload the blame onto the rifle manufacturer. As he had obtained the recommended powder charge with a certain weight bullet from data printed in a magazine, he wants the manufacturer to give him a new rifle, but of course the outfit won’t play ball, for obvious reasons.
Any manufacturer who would guarantee his product with handloads would be crazy. A good handload is as safe as factory load. But there are all kinds and conditions of handloaders; and some alas, are innocent, reckless and careless fellows.
One guy I knew was real hotrodder. He blew up so many rifles that his mates refused to shoot beside him because they didn’t like to have fragments of metal whistling around their ears like shrapnel. Another chap of my acquaintance, pulled the handle of his powder measure twice instead of once, put two charges of BM1 in a case – and blew up his musket.
Yet another guy reloading for his .243 had two cans of powder on his bench – one of W-296 and the other W-760. Yep, you guessed it! He poured the wrong can into his powder measure and dropped a charge of 46gn of W-296 into his cases instead of W- 760. It speaks volumes for the strength of current Model 70 Winchester action that he wasn’t seriously injured. The bolt lugs held, but the receiver was bulged, the scope wrecked and stock blown to pieces.
The world is full of characters who look in a loading manual, pick the hottest load they can find, and then load up a batch of ammunition. Usually they get away with it. Sometimes they don’t.Powder varies from lot to lot. Bullets of the same weight vary in hardness of jacket and core and in amount of bearing surface. An experiment conducted in the American Rifleman many years ago showed that pressure can be increased by up to 8,000 psi just by changing one bullet for another of the same weight.
Some primers are hotter than others. Pressures may be perfectly all right with a given charge of a certain kind and lot of powder and a given bullet, but very high with another make of bullet of the same weight. Some cases have less powder capacity than others and give higher pressures. No two rifles are precisely alike. One may have a loose bore, a long or eroded throat, and a loose chamber. Another may have a tight bore, a short throat, and a tight chamber. With the same charge of powder, the same case, and the same bullet, pressures may run dangerously higher in the second rifle.
Then when a lot of these factors come together – as in the case of a cartridge with a hot lot of powder, a hot primer, a bullet with a very hard core and jacket, and a lot of bearing surface, shot in a rifle with a small chamber, tight throat and tight bore – pressures can really go sky high.
With everyone and his brother manufacturing bullets these days and with everyone making, fitting and chambering barrels there are lot of unknown factors hiding in the woodpile.
No manufacturer could possibly guarantee his product with any and all handloaded ammunition. No magazine could be responsible for results with its suggested loads either.
There is an enormous amount of interest in handloading, and any magazine which ignored that interest would be depriving their readership; but recommendations can only be tentative. Any careful handloader always starts with a load well under maximum, then works up toward maximum gradually, keeping a sharp watch for signs of excessive pressure – sticking cases, primers extruded around the firing pin, excessively flattened primers.
From time to time, this column will print handloading data which to the best of my knowledge, will be safe and even conservative. Nevertheless, anyone who uses the data given does so on his own responsibility.
This article was first published in Sporting Shooter, February 2011.
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