I buy bulk once fired Lake City 5.56 and 7.62 brass and size them once in a small base die to return the cases to minimum SAAMI dimension.

There are times in the past I had to size "some" 7.62 cases with a carbide .45 acp die or a 30-06 die to reduce the body diameter with less effort.

With the older M60 machine gun the case body diameter would expand more and the cases were hard to size in a standard full length die.

Bottom line, if it takes two hands to move the press handle you have fat machine gun brass. This is because Lake City brass is harder and the 7.62 cases are thicker.

Having said that I just finished full length resizing 300 Lake City 7.62 case with a small base die and I did it one handed,