I’ve been looking for more brass – empty cases for the unjargoned – for my .22 Hornet’. (That is pronounced with the accent on the second syllable to give it a European and therefore classier sound.) To my joy, I found 200 pieces of unfired .22 Hornet’ brass, made by Prvi Partizan of Uzice (the town or city, I don’t know how things are categorized there.) (It was the Kingdom of Yugoslavia at the time – 1927 – in the beginning the country now is Serbia. Same physical place. Borders may have been changed to protect the innocent. Or guilty.) This explains the headstamp of PPU. It is also sometimes in Cyrillic and looks like ‘nny’.
All that aside, new brass is new brass. It is properly formed and reasonably ready for loading.
Unless one suffers from obsessive compulsive disorder or is a reloader seeking ultimate accuracy. But I repeat myself. I pulled out my special equipment and proceeded to trim to length, deburr, uniform and de-flash all the primer holes prior to loading.
Allow me to explain. Cartridge brass is ‘formed’ from metallic brass alloy. Such alloy being a combination of copper and zinc, essentially. The alloy can be varied to achieve certain qualities or results. The special qualities desired for cartridge cases are tensile strength to withstand the internal pressures and malleability for forming the initial shape.
Brass cartridge cases are made by high pressure ‘extrusion’ of the metal. Essentially beating on it with a special machine with specially designed ‘dies’ until it fits the shape required.
However, this process often times leaves the length of the individual piece of brass – the empty cartridge – not precisely square at the mouth – where the bullet fits – and not of exact and uniform length.
So one ‘trims’ the case mouth by use of a device which is in reality a small, hand powered lathe. The device is adjustable for length of cut desired. This process both square the case mouth and makes the cases uniformly long. One desires a square mouth so the bullet is free of the case uniformly and no sideways forces are imparted. The length of case allows for consistent resizing of the case and a consistent crimp if desired.
Then, one employs a ‘chamfering tool’ which removes all the leavings of the cutting from the mouth of the case. Among other things, this process keeps the wire edge developed in the cutting process from snagging on other items, like the bullets inserted later and one’s fingers.
Additionally, the flash hole, the small ‘tunnel’ through which the igniting flame of the primer ‘flashes’ to ignite the gun power is normally ‘punched’ through the typically one-eighth inch of brass between the primer pocket and the main chamber (interior) of the case. The hole itself is not always of uniform size and roundness AND there’s a collection of brass hanging on the interior end of the flash hole.
By using a small tool from the interior of the case, through the case mouth, one can make the flash hole uniform in size and circularity AND trim off the bit of hanging brass in the interior.
So why don’t cases come from the factory already trimmed, chamfered and reamed? Mostly cost. I spend probably eight hours doing all that. So the manufacturer would have to add that much pay for a somewhat trained and conscientious worker to do the job. Also, it isn’t always needed. Most commercially manufactured ammunition does not go through the additional steps of processing and shoots quite well in spite of the lack. Did I mention something about OCD conditions earlier.
Following these processes, done by – in this case – your humble correspondent, the finished cases are then weighed on an electronic scale and sorted by weight.
Why? In the instance of a specific caliber – which in general use is more a description of the brass case than the actual diameter of the bore – all cartridge cases are the same external size. For instance, in the instance of the .22 Hornet’ herein involved, the case must have a rim of a specified thickness and external diameter; the body must be a certain external diameter at the juncture of the rim; it must taper at a specified angle for a certain distance, then taper at a greater – also specified – angle to the neck where it must continue to a specified length. All these external dimensions are needed in order for the cartridge to fit into the chamber, but be snug enough in the chamber not to rattle about and possibly react poorly to the sudden internal pressure of firing.
But all those dimensions are external. The internal dimensions can vary to some degree. But when the internal dimensions vary, the internal volume varies. The pressure generated by the burning powder increases in a smaller volume. (Look up Boyle’s Law.) By weighing the individual cases, one can determine a uniformity of internal volume.
Uniformity is one of the great goals of the accurate reloader. The ideal is that everything is exactly the same from loaded round to loaded round. The cases all weigh the same, the bullets all weigh the same, powder charges are all the same and primers are all the same. In reality of course, it doesn’t work that way. (No pun intended.) However, cases can be easily with one percent variation. Commercial bullets are remarkably uniform; weighing them cannot hurt, but may not pay off a great deal. Powder charges can easily be held within one percent uniformity. Primers are pretty much beyond the control of reloaders, but are remarkably uniform as far as manufacturers can manage.
So. Back to the cases and what did I learn?
First. The Cabela’s electronic scale I purchased a year or two ago really isn’t up to the task. Probably the greatest problem is repeated weighings of the same item – one case at random – resulted in several different shown weights. In five readings, the particular case weighed 56.2, 56.3, and 56.4 grains. This without moving the scale, without turning the scale off, and without re-calibrating the scale. The Cabela’s scale is also ‘slow’. By this, I mean the scale takes a bit of time to decide the demonstrated weight of the item. Sometimes, it took several tries to determine if the item in question weighed “56.4” or “56.5” or “56.6” grains. It would show one weight as ‘final’ (a signal icon appears indicating the scale is finished) then change the displayed weight, showing that as ‘final’.
I have recently purchased another Dillon D-Terminator scale. I had one, used it for years with excellent results and dropped it at some point. Note: Dropping electronic equipment is NOT recommended. I bought the Cabela’s unit when my dropped Dillon scale failed, and I succumbed to time panic. Time panic is source material for another blog.
Second. The Lee Precision Reloading shell holder wears out quickly. The holder consists of two parts. The base is a steel machined part which is universal. The variable ‘holder’ is an aluminum piece which screws onto the steel base. The holder is the part that actually fits the case in question. Sadly, being aluminum it tends to wear out on the interior of the top portion of the holder. Consequently, the case doesn’t hold well. Which means the user’s fingers has to take up the slack.
This isn’t so bad for the case length trimming function or the chamfering function. But the flash hole cleaning is really problematic. The cutter gets ‘stuck’ and requires some force to trim the excess from the egress end.
My fingers are worn out. And sore.
The good news is the cases are all prepared and sorted – which only needs be done once. Flash holes and weights do not change with use. The case length can change – usually longer with rifles – and may need trimming again in time.
The good news is that from the 200 cases initially, I have two groups of 50 cases (two boxes) which are within .3 grains difference (lightest to heaviest) each. The other 100 rounds are safe and useful for reloading, but are suited more for non-precision loads; which include small game and predator control and general familiarization with the rifle.
Final note: The above process is most effective when the ammunition is to be used in a specially prepared firearm designed for maximum accuracy. For rifles, this usually includes ‘squaring’ the action, carefully bedding the action and barrel into the stock, trigger work, properly mounted sights (iron or optic) and so forth. For an off the shelf rifle, it usually will not dramatically increase accuracy. But it won’t hurt accuracy either.
In some years of pistol shooting in various disciplines I find pistol cartridges do not appear to benefit from the above functions. I do segregate cases by manufacturer for precision shooting. I have a lingering suspicion even that is mostly superstition.
So if the reader is a new reloader or beginning reloader, please do not feel guilty about not performing any of the above.