When two would-be holdup men confronted drugstore owner Martin Branson as he closed his shop yesterday afternoon, Branson had a surprise for them: He pulled a pistol.

Branson, owner of the St. Jude Apothecary at 2802 Rhode Island Ave. NE., didn't hit anyone with his one shot, but he forced an unarmed suspect to lie on the ground until D.C. police arrived to arrest him. The second suspect, armed with a small-caliber handgun, ran two blocks, basked a cabdriver, Charles Wharton, 55, in the head with the gun and took the taxi.

Branson told police that as he closedhis shop for the day an unarmed man, holding his hand in his pocket as if he had a gun, approached him and ordered him back.

Instead, Branson pulled his gun and loaded its clip, and the man jumped behind a car. The second would-be robber fired two shots at Branson, missing both times.

Branson ordered the man behind the car to stay put and fired a warning shot. The assailant with the gun fled on foot and then commandeered the State Cab taxi.

Police charged Irvin Stephens, 28, of 2701 Robinson Pl. SE, with armed robbery in connection with the incident.