With pressure it is important to realize that once the gate or wall stock freezes there will be no more pressure transferred through the part. This is an important aspect of maintaining uniform nominal wall stock. If a part has varying wall stock the thin areas will tend to freeze, which leads to additional shrink in the thicker areas, which in turn may limit impact on dimensions. Once the gate or wall freezes there is no longer a chance to pack the part. If the area of concern is a thin wall section the wall stock may freeze so fast that there will be very little change in dimensions.