Precision Plus Bushing Bump Neck Sizing Die & three Neck Bushings, .336, .334, .332″ diameter for 308 Win When you order a Precision Plus Bushing Bump Neck Sizing Die Kit, you receive: A top quality, hand polished Forster die to match the caliber of your firearm. *Three standard size bushings, pre-selected by the Forster staff. All bushings are machined to a “smooth as silk” interior finish. Sizing dies for the 308 Win will work to size 307 Win brass as the only difference is the fact that 307 Win is a rimmed cartridge.