The LM Improved Case Plunger fixes a long standing issue with the Dillon stock part. The stock part is great for short pistol cases, but can cause undesired wobble when it pushes rifle cases into the shell plate. This can cause the case to miss the slot entirely causing a myriad of problems.
The Improved Case Plunger addresses this issue by adding needed height to the plunger itself, providing a much larger support area to rifle cases. This reduces or eliminates case wobble on insertion into the plate.
The plunger ships with a new cover, made of Delrin, that eliminates the need to use the Dillon conversion kit adapter. This cover also prevents loaded rounds from entering the shell plate by trapping them before they can be inserted.