Knockout for use while necking a metal container, die system for necking a metal container and method of necking a metal container

A method of necking a metal container comprising:

• (A) moving a necking die over an open end of a metal container, wherein the necking die comprises a working surface having a land, and wherein the metal container comprises;
• (i) an opening;
• and
• (ii) a side wall,
• wherein the side wall has:
• (a) a first inner diameter;
• and
• (b) a second inner diameter;
• wherein the first inner diameter is at least 0.001 inches greater than the second inner diameter;
• (B) Inserting a knockout into the opening of the metal container, wherein the knockout comprises:
• (i) a first knockout outer diameter capable of supporting the first inner diameter of the side wall when the knockout is inserted into the opening of the metal container and when the necking die is over the open end of the metal container;
• and
• (ii) a second knockout outer diameter capable of supporting the second inner diameter of the side wall when the knockout is inserted into the opening of the metal container and when the necking die is over the open end of the metal container,
• wherein the first knockout outer diameter is larger than the second knockout outer diameter,
• (C) removing the necking die from the metal container;
• and
• (D) removing the knockout from the metal container;
• wherein when removing the knockout from the metal container the first knockout outer knockout diameter passes through the second inner diameter of the side wall.

A knockout comprising:

• (A) a first knockout outer diameter capable of supporting a first inner diameter of a side wall of a metal container when the knockout is inserted into an opening of the metal container and when the metal container is being necked with a necking die;
• and
• (B) a second knockout outer diameter capable of supporting a second inner diameter of the side wall when the knockout is inserted into the opening of the metal container and when the metal container is being necked with the necking die,
• wherein the first knockout outer diameter is at least 0.001 inch larger than the second knockout outer diameter.