The carbide 3-die set work fine when using a quality controlled source of brass, like cases fired only in your gun. More care is required when adjusting the bullet seat and crimp die, as seating and crimping occur simultaneously. Bullet diameter control is important when not using the factory crimp. Lee 455 Webley Mark II Pistol 3-Die Set includes Carbide Full Length Sizing Die, Bullet Seating Die, Powder Thru Expanding Die, Universal Shell Holder, Powder Dipper and Instructions/Load Data. Features: Powder through expanding die - notice case neck is expanded and flared with a hollow plug, this allows simultaneous charging with auto-disk powder measure or dipper Hardened steel shell holder Powder measure and charge table Carbide factory crimp die - carbide ring in base resizes any portion of case that exceeds factory new dimensions Floating crimp ring is finger adjustable to provide the perfect crimp