Use Quilted Cryo-Paks in Ammo Boxes
Ammunition that heats up well beyond its normal operating can display over-pressure signs. This is true even of powders that are marketed as being temperature “insensitive”. We strongly recommend that ammo be kept under 90° F, and cooler is better–if you can keep things in the 60-80° range, you’ll find your velocities will stay more consistent with nearly all powder choice. We’ve found a versatile, inexpensive new product that helps keep your ammo cool in hot summer conditions. Kryo-Paks are only about 1/4″ thick and come in pleated grids you can cut to fit your ammo box. We keep one in the bottom of a MTM-100 ammo holder and one on the underside of the box-lid. The 8″x8″ CryoPak “Ice Blanket” costs less than $2 at outlet stores like K-Mart and Walmart. Just keep these in the freezer until needed, then put a layer in the base of your ammo box. It’s also not a bad idea to keep your spare ammo in an insulated cooler, out of the sun.
