Ugly SRT Case Trimmer - Derraco - Shoulder-referenced trimming for maximum precision The Ugly SRT Case Trimmer from Derraco Engineering is a shoulder-referenced case trimmer that trims based on shoulder position rather than the case head. This principle delivers more consistent case lengths than traditional trimmers, because variations in the case head do not affect the final result. For precision shooting sports where every tenth of a millimeter counts, this makes a noticeable difference in ammunition consistency.
The Gen 2 version is designed for use with a cordless drill or drill press. You place the case in the caliber-specific collet, press the case shoulder against the reference point, and the trimmer removes exactly the right amount of material. The result is a clean, straight cut with minimal burr formation.
Premium materials and construction The main body is CNC-milled from 6061 aircraft-grade aluminum (USA-made round stock) and finished with a hard anodization coating that provides ceramic-like wear resistance. Tolerances are held to 0.01mm, ensuring wobble-free operation.
Pressed into the housing is a French-made AB SKF deep groove ball bearing, a high-quality bearing that alone retails for over $20 in Australia. This bearing provides smooth rotation without play, directly contributing to cut quality.
Interchangeable caliber collets The snap-fit collet inserts are manufactured from 303 stainless steel and CNC-turned with high accuracy. Changing calibers is simple: remove the old collet with the included 304 stainless steel removal tool and press the new collet into place with your thumb. Collets are available for more than 30 different calibers, from .17 Hornet to .338 Lapua Magnum.
For gunsmiths and DIY enthusiasts, a blank collet (No.0) is also available in 12L14 free-machining steel. This material is not stainless, but is particularly suitable for machining with a chamber reamer on a lathe.
Lock n Adjust ring for repeatability Each set comes with an adjustable Lock n Adjust ring. Using a feeler gauge or simply a piece of paper, you set the exact trim depth. The clever part of this system: when you change calibers, you lock the ring onto the cutter shank. Later you can reinstall the cutter and immediately continue working with the same setting, without any resetting needed.
M2AL HSS cutting blade The milling blade is manufactured from M2AL HSS (High Speed Steel), a material known for its sharpness and durability. The blade and shank are centerless ground for a sliding fit tolerance of only 0.01mm in the shank hole. This prevents wobble during rotation and ensures a clean, smooth cut on the brass.
As an optional upgrade, a tungsten carbide cutting blade is available for even longer tool life, as well as a 22° inner diameter chamfer cutter for VLD bullets.
Specifications Type: Shoulder-referenced case trimmer (drill type) Main body: 6061 aircraft-grade aluminum, hard anodized Tolerance: 0.01mm Bearing: French AB SKF deep groove ball bearing Collet insert: 303 stainless steel, snap-fit Cutting blade: M2AL HSS, 4-flute Set screws: Brass tip (won't damage case) Available calibers: 30+ different collets Included: Main body with bearing, 1x caliber collet of choice, M2AL-HSS cutting blade, Lock n Adjust ring, collet removal tool (304 stainless), storage packaging with VPI rust inhibitor paper Optional: Extra collets, tungsten carbide cutting blade, 22° chamfer cutter Manufacturer: Derraco Engineering (Australia) 
