take the scope off, check the bases, then using a boresighter, check the scope and make sure its adjusting, tap the scope where it adjusts to see if the reticle jumps around at all(it shouldnt) jar the gun a bit simulating a gun shot checking if its moved on the boresighter.
742 and 7400 have never been wonderfully accurate but I love hearing them being fired off during season, BLAM! BLAM! BLAM! BLAM! BLAM!
oh, and if it has those "see-thru" type scope rings take them off they arent very good