According to Time Life's "The Soviet Air Force at War", it carried 2200lbs with a top speed of 340mph, and a range of... crap, what was it? Something between 1300 and 1600 miles. It had 2x 20mm guns I think fixed in the nose and 2 defensive 12.7mms
Still, 2200 is nothing to sneeze at. Twice that of the Pe-2, basically.