A liquid hydrogen target was bombarded by negative pions of energies 260. 317, 371, and 427 Mev. Positive pions from the reaction pi /sup -/ + p yields pi /sup +/ + pi /sup -/ + n were dete cted by the use of a counter telescope, that selected the pi /sup +/ by its characteristic pi - mu decay. With the 260-Mev beam, pi /sup +/ mesons were counted at 90 deg in the laboratory system. At measured for pi /sup +/ mesons emitted at 60 deg , 90 deg , 125 deg , and 160 deg in the center-of-mass system. The angular distributions are nearly isotropic at 317 and 371 Mev but are peaked forward at 427 Mev. The total cross sections are 0.14 plus or minus 0.10 mbat26O Mev, 0.71 plus or minus 0.17 mb at3l7Mev, 1.93 plus or minus 0.37mb at 371 Mev, and 3.36 plus or minus 0.74 mb at 427 Mev. These results indicate a much larger cross section than the theoretical prediction based on the static model. Reasonable agreement can be obtained by the inclusion of a pion-pion interaction in the production mechanism. (auth)