The lock-n-load o.A.L.Gauge is an easy-to-use and reliable method of regulating seating depth and the resulting "jump" to the rifling.This curved oal gauge works for all autoloader, lever or pump action rifles; all bolt action and single shot firearms.It is not compatible with adapter "d" or short-bodied cases.Note: to use the lock-n-load oal straight gauge, you will need a modified case to fit your firearm's chamber (not included).Type: Overall Length GaugeCaliber: Multi-CaliberSize: CurvedQuantity: 1Weight: 0.22 lbsFunction: MeasureCompatible With: .17 Remington - 500 Nitro