A multilayer, heat-shrinkable film contains at least one semi-crystalline polyamide selected from the group consisting of polyamide 6, polyamide 66, polyamide 6/66, and polyamide 6/12. The film may have a total semi-crystalline polyamide content of at least 35 volume percent, based on total film volume, and a total free shrink at 185.degree. F. of at least 35 percent. The film may have an FTIR Transmission Absorbance A.sub.1199/A.sub.1170 ratio of up to 1.65. The film may be a retortable film, capable of being used in a process for preparing a retorted packaged product. A process for making a heat-shrinkable annular film containing the semi-crystalline polyamide comprises extruding an annular extrudate downward from an annular die, quenching the annular extrudate by applying a quenching liquid to the annular extrudate, reheating the extrudate to an orientation temperature, and orienting the reheated annular extrudate while the reheated annular extrudate is in the solid state, the orientation being carried out with a total orientation factor of at least 2, to produce a film having a total free shrink at 185.degree. F. of at least 10 percent.

 
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