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Brass Case Trimming Part 2


There are a few different ways to actually trim your brass. Starting at the cheaper end, we have Lee Precision’s Case Length Gauge and Shell Holder, which allows you to screw a set length gauge for a certain caliber into a cutter and trim to the set length. It’s designed to bottom out on the shell holder when the length is reached. Lee Precision’s other option is the Quick Trim Die, where you place a brass case inside a caliber-specific trim die, and then place the die into a standard reloading press. Then, with a handheld cutter, you trim the case down using the trim die to set the length.

Moving up the expense scale we start to see lathe-type trimmers appear from most of the mainstream manufacturers. These hold the case by the case head using a collet, and the cutter is guided by a pilot into the neck where it starts cutting the neck down. Some of these types of lathes, such as the Forster, can also double up as outside neck turners, and most will also handle inside neck chamfering as well.

As the cost of the trimmer increases, so too does the range of accessory options, which include things like micrometer gauges for ease of use when setting custom case lengths. You may use these for trimming your brass to the shortest case in the batch. The micrometer-type attachments help to make minute alterations to trim length, and also aid repeatability when using the trimmer from session to session, as you can note the actual settings on the micrometer. Some of the more custom-grade trimmers, like the LE Wilson, dispense with a collet for holding the case and instead use a case holder. This is a short piece of round bar with a caliber-specific hole in the middle in which the case is placed and tapped home for a tight fit. The case holder is then placed onto two rods on the trimmer bed, and a clamp is employed over the top to hold the complete assembly in place.

Other types of trimmers are the ones that can be used in conjunction with a battery-operated power drill. These have a hex shaft rod on them that the drill bites onto. These usually slip over the top of the case neck and trim the neck down until a built-in stop hits the shoulder and bottoms out the cutter. Slight variations on this type of cutter also allow us to trim, deburr and chamfer the neck at the same time, all in one operation. As already mentioned, some trimmers also allow us to neck turn with outside neck turning attachments, and others allow us to use inside neck reamers for the removal of internal ‘donuts’ (this will be covered in more depth in a future issue.

There are pros and cons to all of the above trimmers. Some will only cut to a set length and therefore are not as adaptable as others. Some are caliber specific so you will need to get a few different cutters if you shoot a few different calibers. Some are just more expensive than others. Like most tools in the reloading world, it’s a very personal choice as to which one you use, and to a certain extent the type of shooting and caliber used can determine the type of cutter you might use.There is no such thing as a bad trimmer, but some features are more desirable than others – for example, to be able to hold the case in a case holder while trimming leaves both hands free for ease of operation

Once you’ve chamfered and deburred the cases, you’ve completed the case preparation process. Now, you are ready to begin assembling a quality reloading brass that will give a high level of accuracy and precision in your rifle. The next article in this series will examine the different types of case lubes available that help your carefully-prepped cases work correctly inside reloading dies.