High Grade Bullet & Headspace Comparator Set by Derraco Engineering

Material: Bushing holding body: 303 Stainless steel. Headspace & bullet comparator bushings: 6061 Aircraft grade aluminum alloy. Surface color-coded and Type II hard anodized with a ceramic-like wear-resistant surface. Compatible caliper jaw thickness: ≤4.70mm Bullet bushing sizes: .17, 20, 22, 24, 25, 26, 27, 28, 30, 33, 35, 37, 41, 45 Headspace busing size: .330, 350, 375, 400, 420

• Screw-on bushing design. Stainless Steel bushing holding body. Better concentricity and consistency than the H brand or others
• High-grade CNC machining ensures precise, consistent, and beautifully finished parts
• Color-coded bushings with a ceramic-like Type II hard anodic coating provide a durable finish and make it easy to identify calibers for user convenience
• A nice tin box is included for convenient bushing storage
• Headspace gauge bushings were individually pin-checked with Go=-12μm(-half thou), No-Go=+12μm(+half thou)
• We're a small business from Australia called Derraco Engineering. We take our time designing and making our products, making sure we do it right without taking any shortcuts. We hope that once you try our stuff, you'll remember our name.
• Our bullet comparator bushings are designed according to bore riflings. They are not supposed to be the exact size such as .2200 or.3000. Riflings ID is always a bit smaller than the bullet diameter otherwise won't form the gas seal.
• Our headspace gauge bushings are in exact marked size as this was made according to SAAMI headspace gauge standards. All our bushings do not have any ID chamfer and they were not sand blasted like some others. The clean sharp edge is designed for accurate measuring of bullet and shoulder contours.
• Tip for choosing headspace gauges: measure the neck OD and shoulder OD. The best measuring point should be close to the middle line of the neck OD and Shoulder OD. The middle line of the shoulder taper. Therefore you should just choose which ever headspace bushing with ID nearest to the shoulder taper's middle line diameter.