Preheat your oven to 350 degrees.
Grind your graham crackers to make a fine crumb. Mix them with your butter and sugar and pack into the bottom of a 8x8 baking pan and place in oven and bake for 10 minutes.
Pour heavy cream into a large mixing bowl and whip over high speed until stiff peaks form (about 12-15 minutes).
Combine your sweetened condensed milk, lime juice and lime zest in a large bowl.
Pour your whipped cream on top of your condensed milk mixture and fold together till thoroughly mixed.
Pour 1/3 of your ice cream into a 3 qt container. Scoop about 1/4 cup of your pie crust and sprinkle over the ice cream. Repeat with another 1/3 of your ice cream and another 1/4 cup of pie crust. And the final bit of ice cream and pie crust.
Cover tightly and place in your freezer for at least 6 hours, up to overnight.