Page:Tactics (Balck 1915).djvu/198

 (b) Influence of the Error in Estimating the Range.

At short ranges an error of estimation is offset by the flatness of the trajectory. Lieutenant-General Rohne used a probable error in estimation of 1/8 (12.5%) of the range in his computations. The Swiss Firing Regulations of 1905 count on an error of 100 m. at 500 m., 200 m. at 500 to 1,000 m., 300 m. at ranges over 1,000 m., and the average is taken to be 1/5 of the range, or 20%. For measurements with range finding instruments see p. 146, supra.

Elevation 800  -  -  Excellent shots  {  Limit of the Rifle    '98  -  Fair        "    {  probable error               —  —  —     Poor        "    {  of estimation.

Elevation 1000. Rifle     '98.