For sleeving applications, you want to establish the correct drawdown ratio and draw ratio balance for the material being extruded. Next, you want to have a land that is appropriate for the die gap. For pressure extrusion, you need an opening that is sufficient for the core to pass through, but not large enough to allow leaking inside the tip. Generally speaking, sleeving tooling improves wall thickness control, and pressure tooling is better for faster line speeds