Calculating Artillery Piece Efficiency

(Created July 2016)

Reference:
Brassey's Artillery of the World, edited by Shelford Bidwell

A quick formula, put forth in the book referenced above is:

E = Shell Weight * Range \ Equipment Weight

A quick calculation of the major US 155mm howitzers since World War II shows:

155mm M1/M114 Howitzer: 10.8% Efficient
155mm M198 Howitzer: 13.1% Efficient
155mm M777 Howitzer: 23.9% Efficient