BLUF: When emplacing the 60mm mortar in freezing weather, protect the baseplate by placing dry bags of sand or snow beneath it to prevent cracking.
Operators and crew members, when you emplace the 60mm mortar baseplate on frozen ground, the cold temperature may make the metal brittle. The combination of brittle metal and the tremendous shock that the baseplate receives when a round is fired may cause the baseplate to crack.
WP 0018-2 of TM 9-1010-233-10 (Jul 16) tells you to emplace the 60mm mortar in frozen ground by loosening the ground to seat baseplate spades and bipod feet or, as an alternative, to use tree limbs, branches or sandbags to emplace the mortar. Because that’s not very specific, the next TM update will provide more details.
Till then, here’s what you need to know. You can position the mortar using one of the following methods:
- Use a combination of logs lashed together and bags of either dry sand or snow beneath the baseplate to provide the weapon with a solid, yet resilient shock-absorbing base.
Graphic depiction of best ways to emplace 60mm mortar in extreme cold
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- Use a combination of sandbags (or bags filled with snow), small stones and a box filled with dirt to create a backstopped firing position that cushions the baseplate yet also provides a solid, shock-absorbing emplacement.
- An alternate but less preferable method is to make a mat out of brush under the baseplate. The brush mat should be a minimum of 3 ½ inches thick when compressed. If available, snowshoes can be placed under the bipods to help prevent the bipods from sinking in the snow. As with the first two methods, a solid foundation should be constructed beneath the brush to help with shock absorption.