Redding Reloading Case Neck Gauge .17 .338 Caliber. This case neck gauge gives you a fast and easy way to sort your cartridge cases by the thickness and uniformity of the neck wall. With two mandrel sizes available this case neck gauge accommodates the measurement of all cases ranging from .17 caliber to .338 caliber Specifications for Redding Reloading Case Neck Gauge: Manufacturer: Redding Reloading Projectile Caliber: .17 Caliber Package Contents: Redding Reloading Case Neck Gauge Redding Reloading 26400: Case Neck Gauge .17 .338 Caliber