1.1 This test method covers the measurement of unrestrained drying shrinkage of masonry mortars. 1.2 This test method is applicable to Specification C 270 Type N, Type S, and Type M mortars under the property or proportion specifications. Due to the tendency to damage lower strength specimens during demolding, it is not applicable to lower strength mortars, such as Type O mortars. 1.3 This test method is intended for rese