On the basis of outside dimensions being the same, any variation in weight must be more or less reflected by the inside dimensions. Start by comparing the powder capacity with your ‘regular’ models. So, unless you’ve stuffed this particular case type before, there are a number of advisable pre-load tests. It is also free to ignore SAAMI or CIP specs with regard to operating pressures. It is not made with the reloader in mind, but rather for single use and to withstand the rigours of a service life and extreme operating conditions. Others suggest that case capacities are not dissimilar to commercial not my experience! The former are mostly designed to suit a different set of parameters. Some claim that military brass is tougher than commercial and therefore offers an increased number of reloads. Moving on to the assembly process, there are some further issues that must be addressed. A number of dedicated uniforming tools are offered to normalise the base and sides and flare the mouth. The exposed pocket now needs extra attention, before priming can take place. Saying that, it’s possible to reload Berdan cases, using either a hydraulic or levertype de-capper, and suitable primers are also available but why bother, as it’s a royal pain? Regardless, a crimped-in primer can require considerable force to remove and for that reason tougher de-cap pins are offered. However, these days more ammo is being produced with the single, central hole Boxer system. So, your standard, single/central de-priming pin is going to get smashed up if that’s the case. Military brass is more likely to be cursed with Berdan priming twin, offset flash holes. We’ve already examined the case head, but a look inside would be advisable. A finishing neck and shoulder anneal is then applied and the finished case chemically washed. This is the final mechanical process, the tool entering through the primer pocket. A cut/trim tool now removes the excess neck material and chamfers the mouth of the neck. Washing and annealing are now the precursor to a two or three stage taper/shoulder form process. The final finishing of the rim/groove is usually completed by a machining process. In some instances, the bunt/punch are part of a compound tool that also performs a ‘start’for the rim/extractor groove. A forming punch is driven into the centre of the head to create the pocket before a tool called a bunt is used to pressure engrave the headstamp details. The primer pocket and head details are next. The results of this therefore has to be heat-treated by annealing and chemically washed between some of the production stages, in order to restore its working properties. As each forming process works the brass, so it gets harder and more brittle. To tidy the ‘neck’, they are often ‘pinch’ trimmed between draws. These now enter what may be a two, three or four stage ‘deep-draw’ process in which the walls are progressively elongated (and therefore thinned). These are fed into a multi-punch die set in a powered press that outputs thick walled ‘cups’. The most common mass production processes start with reels of ‘cartridge brass’ that are slit into strip reels. The specific method of manufacture, subsequent heat treatment processes and the final physical dimensions all have a role to play in both the life and performance. However, the recipe is only part of the final product. Copper, zinc and tracesĬartridge Brass (C260)’, is an alloy of 70/30% Copper and Zinc, although subtle variations do exist. Two common forms of primer retention are a ring crimp or three or four point stakes. The primer pocket will reveal evidence of intended military use in the form of sealants, crimps or both. Colour will often give us a clue as to the nature of the brass, with dark shades often signifying production intended for military use. Don’t forget to weed out steel and aluminium types, as they have no place for our needs! The headstamp will (mostly) establish the origins of the manufacture and allow us to weed out any aliens. Noting the appearance and eyeballing the primer pocket are the key start points. So, what are the physical considerations between military and civilian brass, with respect to reloading? The two obvious candidates being. Not all cartridge cases are born the same.
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