New Adjustable-Length Jacket Trim Die
A new die that can trim existing bullet jackets to various adjustable shorter lengths, without changing punches, is now available from Corbin. The die, called ET-1 for Expand/Trim One-die Set, is available in type -R for reloading presses. The new ET-2 is used for Corbin hand and power presses.
- Jacket is the same diameter after trimming length
- Nearly any shorter length may be obtained quickly
- Trim takes place as punch enters the die mouth
- Length is set with a stop screw adjustment
- Stock jackets of a single length, use for lighter weights
- Trim fired .22 cases (LR, Stinger, or 22 WMR) to precise length
The ET-1 is normally used for drawn commercial jackets, made from a strip of copper or gilding metal. Copper tubing can be too difficult to pinch trim without the power of a Hydro-Press. Steel, hard brass or other unusual jacket materials should not be used without sending samples to Corbin for testing and evaluation. Doing so may damage the die or punch.
To operate, simply adjust the threaded stop screw at the top of the die so that the desired length of jacket is within the die body, and the surplus to be cut off projects from the die mouth. The punch pushes the jacket into the die. When the jacket head comes up against the end of the adjustable stop, the shoulder of the punch is driven further into the jacket mouth, expanding it. The expanded portion slips over the shoulder on the punch and is pinched off against the hard die mouth. The surplus material is stripped of the punch by a tube and disk stripper assembly, provided with the type -R, -M, and -S dies. The type -H dies require the use of the SK-1-H Stripper Kit, which comes with one caliber plate. The same kit can be used with other calibers by purchasing additional caliber plates (SK-P-H).
Expand/Trim die, or ET-1, cuts the jacket by pinch trimming it against the hardened die mouth, as the jacket is pushed over a shoulder on the punch, which expands the jacket outward so it can be sheared off between the punch shoulder and the die face. This trim method is faster and more precise than using a separate cutting tool such as might be found in a lathe or other rotating machine tool. Push the jacket in, press on the die handle, and the job is finished.
In order to assure success, you must send a dozen sample jackets of the exact lot to be pinch trimmed. If you do not sent samples, then we must use our jackets, which may have different spring-back and stretching characteristics than yours. Therefore, although our trimmed sample jackets may show perfect conformity, the quality or dimensions of a randomly choosen jacket may show greatly varying results with the same die. Aways send the sample jacket you will be using.
For faster, more automated operation in the Corbin CSP-1 press, Hydro-Press, Corbin CSP-2 press, or Hydro Junior, the new ET-2 ram-mounted self-ejecting and self-stripping die set is recommended. This die does not require stripper kits or ejectors, and is much faster to operate than the ET-1. It does not have the same wide range of adjustment, however. It can be ordered in a "short" or pistol trim, and a "long" or rifle trim. It is recommended for removal of .25 or less inches in a single pass (multiple passes can be made). The minimum trim can be quite short, virtually gas check length, but the longest jacket trim on the same die/punch setup will then be limited to longer pistol lengths (not rifle lengths). The main difference is the geometry of the internal punch, which has a limited amount of travel adjustment within the ram for a given configuration.
For high volume trimming, using special low wear materials, the ET-2-HC "commercial" version is a better choice. See jacket trimmers page for more information and pictures.
Send your sample bullet jackets to:
CORBIN
PO Box 2659
600 Industrial Circle
White City, OR 97503 USA
A new die that can trim existing bullet jackets to various adjustable shorter lengths, without changing punches, is now available from Corbin. The die, called ET-1 for Expand/Trim One-die Set, is available in type -R for reloading presses. The new ET-2 is used for Corbin hand and power presses.
