Lee Factory Rifle Crimp Die .356-358

The Lee Factory Rifle Crimp Die .356-358 (Model 90904) is a precision reloading tool engineered to deliver firm, consistent bullet seating that measurably improves cartridge accuracy and velocity uniformity. Unlike standard dies that allow bullet movement within the case, this factory crimp die locks the projectile in place with substantially greater force, establishing a higher initial pressure curve that translates to tighter shot groups and reduced velocity spread downrange.

The crimping action works on .356–.358 caliber bullets regardless of whether the projectile features a traditional crimp groove. Field testing has demonstrated that even bullets without factory crimp grooves produce more accurate results when processed through this die, because the firm grip prevents bullet setback during firing and ensures pressure builds consistently to the intended threshold. This mechanism eliminates the velocity variation that stems from inconsistent bullet hold, delivering the uniform pressure curve that serious rifle shooters depend on for precision loads. The die dimensions (2 x 2 x 4.75 inches) and 0.38 lb weight make it compact and easy to integrate into standard single-stage or progressive reloading presses.

Handloaders working with .356–.358 caliber rifle cartridges—including wildcats and standard magnum rounds—benefit most from this tool. Whether developing precision loads for long-range competition, match ammunition, or hunting rifles where shot-to-shot consistency matters, the factory crimp die addresses a real weak point in many reloading setups: the final step that locks the bullet securely in place. Lee Precision's straightforward design integrates into most press configurations without requiring adapter sleeves or special tooling.

Factory crimp dies occupy a specific role in the reloading chain: they're typically the final operation after seating, applied to rounds that have already received their powder charge and primer. This approach gives the reloader independent control over bullet seating force and crimp pressure, allowing optimization for the specific rifle and load being developed.