Expander mandrels


SKU: MANDREL Categories: ,


Our expander mandrels are available in 0.0005″ increments.

The purpose of the expander mandrel is to ensure a precise and consistent inner diameter of the case neck. This is crucial because it directly affects the bullet’s fit and alignment with the barrel of the firearm. A proper fit and alignment contribute to accuracy and consistency in shooting.

During the reloading process, the case is placed on the expander mandrel, and the reloading press is activated. As the press exerts downward force, the mandrel expands the case neck by gently pushing against its inner walls. This expansion process is controlled and precise, ensuring that the case neck maintains a uniform and consistent inner diameter.

After expansion with expander mandrel, and the case can then be filled with powder and fitted with a bullet. The expanded case neck allows for easy bullet insertion and ensures a secure grip on the bullet without excessive tension or looseness.

By using an expander mandrel, precision ammunition reloaders can achieve consistent and reliable results in terms of bullet seating depth, bullet release, and overall shooting performance.

Our expander mandrels are compatible with 21st Century expander mandrel dies.  Our expander mandrels are made of 300 Series Stainless Steel and coated with Armoloy.

The benefits of Armoloy coating include:

  1. Wear Resistance: The Armoloy coating significantly increases the surface hardness of the treated parts, improving their resistance to wear, abrasion, and friction. This helps extend the service life of the components and reduces the need for frequent replacements.
  2. Low Friction: The smooth and lubricious nature of the Armoloy coating reduces friction between moving parts, resulting in smoother operation, reduced heat generation, and improved overall efficiency.
  3. Chemical Resistance: Armoloy-coated surfaces are resistant to various chemicals, solvents, and cleaning agents.

Try our expander mandrel dies.  Our dies are cartridge family specific and size the base of the case as you expand the necks.  https://www.shootsmallgroups.com/product/expanding-mandrel-dies/


Additional information


.2220, .2225, .2550, .2555, .241, .2415, .262, .2625, .282, .2825, .306, .3065