TheLyman carbide matrix for formatting the shell neck for .300 caliber Winchester Magnum has a hardened body and an ultra-hard carbide expander. The carbide matrix extends the life of the shell and allows the shell to fit perfectly into the chamber of our weapon.
Like a standard expander, the matrix does not stretch the shell, so it improves the precision of formatting and extends the life of the shell, According to many shooters, the two-stage matrix for formatting the neck of the shell noticeably improves the efficiency and repeatability of elaborated ammunition.
Lyman carbide matrix for formatting the neck of the .300 Win Mag shell - professional elaboration accessories in the Kolba store
The first step expands the inside of the shell neck to slightly smaller than the diameter of the bullet, ensuring an optimal fit of the shell neck. The second step expands the inlet of the shell to the diameter of the bullet or slightly above. This allows the bullet to be placed perfectly centered and axial to the shell neck. The carbide mandrel is very hard and perfectly smooth, so it easily passes through the shell neck, causing the shell to stretch easily and precisely. Thus, the carbide die reduces the degree of trim in the shell, which, of course, contributes to longer shell life.
According to the manufacturer, the working surfaces made of tungsten carbide do not require the use of shell lubricants.