This Lee Precision Case Length Gauge is the easiest way to trim 7x57 Mauser cases to the proper length while squaring case mouths at the same time. The hardened steel Case Length Gauge is precisely sized to produce cases perfectly trimmed to the SAAMI (Sporting Arms and Ammunition Manufacturers' Institute) standard length. The specially designed shell holder helps keep everything square.
The Lee Case Length Gauge and Shell holder works in conjunction with LEE's Cutter and Lock Stud (as shown in the image below), and with the LEE Cutter with Ball Grip and /or LEE Zip Trim to produce consistently trimmed and squared cases with no guesswork and no measuring required.
If you're looking for a simple, no hassle way to quickly trim and square your cases to SAAMI standards, this is the tool for you.