Yes, I've had this as well, it pulls to left or right in varying degrees sometines as much as 10 degrees, for no apparant reason, no heading changes in the uboat, matched target ship's base course and speed. firing at it with the gun bearing roughly 300 degrees. I think it's a stock bug and can be very annoying when you're trying to hit a small target or a very distant one.
doesn't matter so much when firing at a C3 from 700m, it's bigger than the broadside of a barn, but when trying to take out a pursuing flower corvette at 5000 meters it's life-threatening