Brownells 75th Anniversary - A Shooting Heritage

Choosing A Case Trimmer

Looking for your first case trimmer or looking to replace or grade your current one?

Trimming is required on most cases because of the normal case lengthening that occurs during firing and resizing. Length trimming is often needed on cases that have been formed from a parent case. Many case trimmers can perform a multitude of other tasks by adding accessories. Factors in choosing a trimmer can include your budget, the volume of cases you are trimming, the other case preparation tasks you want the trimmer to handle, and the quality of trimming that you will accept. The following are a few questions that you should consider when choosing a case trimmer.

  1. How accurately will the tool trim each case to the pre-set length?
  2. How square is the cut made to the case mouth with respect to the axis of the case?
  3. How fast does the trimmer cut? (How aggressive is the cutter?)
  4. How easy is it to load and unload cases from the trimmer?
  5. How clean of a cut does the trimmer make?
  6. What other functions can the case trimmer perform?
  7. What caliber pilots does the trimmer manufacturer offer and what case head sizes (or cartridges) will the trimmer accept?

There are basically only a few basic types of trimmers. Let’s discuss the qualities of the different styles of trimmers and discuss in detail a few ofthe trimmers that we know work well from personal experience.

Collet Style Trimmers

Two collet style trimmer that we are most familiar with are the Forster and Redding Case Trimmers. The collet style trimmer uses a multi-stepped collet head that holds the case head securely while a caliber specific pilot supports the case neck. The pilot also squares the case mouth to the cutter. Collet style trimmers are easy to use, moderately easy to load and unload, and provide a clean square cut. The focus when using a collet style trimmer is to maintain a consistent case length from one case to the next. You need to make sure the case is held tight against the step in the collet when tightening to prevent the case from moving forward in the collet. If any cases move forward as the collet is closed it can result in a different trim length. This is usually easy to control by making sure your cases are held firmly against the collet face, then lightly tighten the collet and align the pilot with the case mouth while moving the pilot into the case. Then tighten the collet firmly. Always maintain pressure on the case back towards the collet to insure that the case head is tight against the stepped base of the collet so as to achieve a consistent length cut.

One noteworthy difference between the Forster and Redding trimmers is that the cutter assembly turns on the Forster as do most trimmers but the Redding trimmer keeps the cutter stationary while the case mounted in the collet turns.

Redding Features:

  • Two models available: Model 2400 and Model 1400-XT
  • Sturdy cast iron frame drilled for mounting to a bench or plate. New design accommodates all of the new long action cartridges.
  • Includes 6 pilots, neck cleaning brushes, and large/small primer pocket cleaners.
  • TiN coated cutter (optional .17/.20 caliber TiN cutter available)
  • Power adapter available
  • Micrometer adjustable version available on Model 2400 (increments of .001”).
  • Push button collet lock
  • Storage positions on base to handle 6 pilots
  • One model handles up to 3” case length (Model 1400) while their other model handles up to 3.250” in length (Model 2400)
  • Universal collet that fits most popular cases (no others to buy).

Redding Applications:

  • Great for rifle as well as handgun cartridges. Wide range of pilots to accommodate almost all calibers from .17 caliber thru .475.
  • Fairly quick to load and unload. Power adapter makes it suitable for medium volume reloaders that would be trimming a hundred to a few hundred cases in a batch.
  • Doesn’t currently have provisions for inside neck reaming or military crimp removal.

Forster Features:

  • Three models available: Original, Classic, and .50 BMG trimmer. There is also a power case trimmer discussed further in the article.
  • All models utilize and aluminum frame that can be mounted to a workbench or plate.
  • Original and Classic features a collet assembly that utilizes Brown & Sharp type collets.
  • Original utilizes 4 collets for most rifle and pistol cartridges. If trimming 9mm Luger or shorter cases, you will need the optional shorter base.
  • Classic is designed for large caliber cartridges used in popular large game rifles and classic black powder cartridges. Utilizes 4 larger collets that will only work with the Classic model. Will accommodate cases in length from 1-7/8” thru 4-1/8”.
  • .50 BMG Model is designed specifically for the .50 BMG cartridge and comes complete with pilot and rim holder (no collet needed).
  • All Forster trimmers feature a quick turn locking mechanism for the case head.
  • Power adapter available. Trim up to 200 cases per hour.
  • Wide range of pilots available from .17 caliber thru .50 caliber including some very rare European calibers.
  • .17 caliber cutter available
  • Optional accessories include inside neck reamers, outside neck turning tool attachment, primer pocket cleaner, universal hollow pointer, primer pocket chamfering tool (military crimp removal), and an accessory case.

Forster Applications:

  • A real good choice for almost any reloader regardless of quantity of cases trimming.
  • Versatility in the reloading chores is a good reason to choose this trimmer.
  • Supports the widest variety of cartridges of any trimmer we know of!

Wilson Case Trimmer

The L.E. Wilson Case Trimmer is unique from any other style of case trimmer. The Wilson trimmer uses case holders that hold the case on the taper of the case and doesn’t utilize pilots. The case holder rests on machined rails that also hold the cutter shaft housing. This insures the case is aligned square to the cutter face. The case head, which protrudes out of one end of the case holder, is positioned against an adjustable stop screw. The user rotates the cutter using the handle or a power adaptor until the cutter has cut to the full length of its travel. This case trimmer trims cases squarely and to a very consistent length. This trimmer has many accessories for performing other case prep work including neck reaming, case mouth deburring, and primer pocket reaming (military crimp removal). The Wilson trimmer is very easy to load and unload and extremely easy to adjust for case length. We think it is the most accurate case trimmer made with respect to consistency of case length. It is also a good choice for moderately high volume reloaders because of its quick load feature. Best when purchased as a complete kit which includes the trimmer and a Sinclair stand with a built-in clamping feature to hold down the case holder.

Wilson Features:

  • Most accurate of all trimmers we have ever used
  • No pilots required
  • Positive case length assured because of design
  • Very clean cutting
  • Easiest case trimmer to setup for length
  • Accessories available for inside neck reaming, case mouth deburring, and primer pocket reaming (military crimp removal).
  • Wide range of case holders available for most popular rifle cases.
  • Q-Style case holder recommended for rimmed pistol cases
  • Micrometer version available (Sinclair Model #05-475). Adjusts in increments of .001”.
  • Available in a Sinclair kit which includes the Sinclair Mounting Stand and SharkFin Clamping Feature (Model #05-425)

Wilson Application:

  • Primarily designed for most popular competition and hunting cartridges.
  • This is the preferred trimmer if you are mainly going to trim bottleneck cartridges or rimmed pistol cartridges.
  • Great for moderate to high volume reloaders.
  • We highly recommend considering this trimmer if it fits the cartridge families you plan on loading for.

Hornady Cam-Lock Case Trimmer

The Hornady Cam-Lock Case Trimmer is similar to a collet style trimmer but utilizes shellholders in place of collets to hold the case head. The Cam-Lock shellholder system features a lever that you turn to lock the case securely in the shellholder so you can feed the case cleanly onto the cutter pilot. This unique system insures you will get the same case length each time.

Hornady Features:

  • Utilizes standard Hornady shellholders
  • Unique one finger case cam lock.
  • Large diameter, replaceable cutting head trims cases up to .50 caliber.
  • Optional .17 caliber/pilot combination available
  • Heavy-duty cast iron frame designed for bolting to a workbench or plate. New taller design that is more ergonomic for faster trimming.
  • Micrometer adjustable cutter included.
  • Chamfer/Deburring tools available
  • Trimmer includes seven of the most popular caliber pilots.
  • Power adapter available.
  • Trimmer pilots available for .17 caliber thru .50 caliber.
  • Trims cases up to 3.400” in case length.

Hornady Application:

  • Designed for most popular rifle and pistol cartridges.
  • The Cam-Lock feature makes this a favorite choice of ours.
  • Note: Forster inside neck reamers will fit the Hornady trimmer as well as Forster universal hollow pointers (both use a 3/16” shaft. The ability to utilize these accessories increases the value of the Hornady trimmer for moderate to high volume reloaders.

RCBS Trim Pro Manual Case Trimmer

The RCBS Trim Pro Case Trimmer is another unique case trimmer because of the way it holds the case head. It incorporates shell plates in its design and a spring-loaded release lever that locks and releases the case in the shell plate. Cases are aligned and supported by a pilot in the cutter shaft. The cutting shaft features a micrometer fine-adjustment bushing for setting the exact trim length.

RCBS Trim Pro Features:

  • Utilizes unique RCBS shell plates (they call them shellholders but people might think you can use regular shellholders).
  • Very quick loading and release spring-loaded mechanism.
  • Large diameter, replaceable cutting head trims cases up to .50 caliber.
  • Available as a kit with 4 shell plates and 9 pilots or you can get it without and select only the pilots and shellholders you need.
  • Die cast frame
  • Power adapter available.
  • Trimmer pilots available for .17 caliber thru .50 caliber.
  • Neck turning attachment available.
  • Can be upgraded to a Trim Pro Power Case Trimmer by adding the power unit.

RCBS Application:

  • Will work with most rifle and pistol cartridges.
  • The spring-loaded mechanism for holding the cases is very comfortable to use.
  • No inside neck reamers available.
  • Good high volume case trimmer.

Power Trimmers

A great power trimmer is the RCBS Trim Pro Power Case Trimmer. This is basically an RCBS Hand Case Trimmer mounted to a motorized unit that drives the trimmer cutter. The trimmer cutter is controlled with a spring-fed mechanism that is easy to use. This leaves your hands free for other activities while the case is being trimmed. The collet closure on this trimmer has a large handle that is quick and easy to use. This is a great trimmer for high volume shooters and fairly easy to setup. Also available in 240 VAC-EUR for our friends overseas.

Another power trimmer is the Forster Power Case Trimmer. This trimmer is actually a base and cutter that works in conjunction with a drill press. The base of the trimmer mounts to a drill press table and holds the collets, as would a regular trimmer only in a vertical orientation. The cutter is held in the drill press chuck and is lowered onto the case neck. Works well but not used by a lot of reloaders. Great for high volume reloaders if you have a small drill press, but these are relatively inexpensive these days at most building centers. The Power Case Trimmer uses the same accessories as the Original Forster Trimmer.

Finally, a third option for power case trimming is the Gracey Trimmer, which has its origin in the High Power shooting arena. The Gracey trimmer utilizes the case shoulder to hold the case mouth a consistent distance from the cutter. The case is pushed into a centering guide that is cut to match the shoulder datum dimension. The cutter trims the case mouth until the case’s shoulder pushes up against the centering guide. This trimmer works off of the premise that all fired cases will have the same length from case head to datum after having been fired or having been full length resized. Thus, if each case contacts the datum in the same place than any excess material cut off will result in each case having the same overall length. When using a Gracey trimmer that has been setup, a reloader can process a lot of cases in a short time. We think this trimmer is a well-made piece of gear but find it to be extremely hard and time consuming to setup. There are a couple of other “cottage industry” power trimmers that we have seen over the years but haven’t had a chance to use. Some of these have been readily accepted by the large volume reloaders.

Trimmer Maintenance

There isn’t much required to maintain your case trimmer. Keep the cutter clean of chips, oil the cutter shaft where it rides in the bearing head, and oil the crank handle. The cutters are hardened tool steel and last quite a long time, especially since they are cutting a relatively soft material. Most can be re-sharpened or simply replaced if you ever wear one down. Cleaning chips and shavings frequently will insure a good clean cut. You usually will be able to tell when your cutter needs replaced or sharpened as they will quit cutting and begin tearing at the case mouth leaving a very rough finish.

Case Mouth Deburring Tools

Always make sure you debur the case mouth inside and out after case trimming. This is critical for accuracy. Case mouth deburring tools are used to remove the sharp edge off of case mouths that is created after trimming or neck turning. This sharp edge can effect bullet entry into the case and also damage the bullet jacket when the bullet is seated into the case neck. Most case mouth deburring tools are double-ended. One end is used to debur and chamfer the inside of the case mouth while the other end is used for the outside edge.

Standard case mouth deburring tools are machined with a 45-degree angle. Sinclair makes a carbide single-ended deburring tool that has a 28-degree angled cutter, which provides a better entry angle for the bullet, especially when using VLD bullets. This tool is also great for standard boat tail bullets as well as flat base bullets. When using this tool, you will still need a standard case mouth deburring tool to debur the outside.

We prefer using the Sinclair Carbide deburring tool, the Wilson deburring tool or the Forster tool. This is one operation we would recommend powering if you are going to prepare any significant amount of cases. There is a Sinclair Power Adapter that fits Wilson, RCBS, and Forster deburring tool cutters that you can use in a drill, power screwdriver, or drill press. It really makes short work of deburring case mouths and is invaluable to moderate for high volume reloaders.


We hope this outline of some of the important features of a few of the case trimmers helps you in your selection of a case trimmer. Make sure the trimmer you chose not only takes care of your current trimming needs but plan for that next cartridge you will be reloading also.

Our personal recommendation is the Wilson Case Trimmer because we like the way it holds and aligns the case, but we realize it doesn’t fit everyone’s needs. Our second recommendation would be to select a Hornady, Forster, or RCBS Case Trimmer.

If you need any help when selecting a case trimmer, just give our friendly and knowledgeable tech staff a call and we’ll do our best for you.