This is an interesting question, and the answer isn't as obvious as at first might appear. The HS barrel sits in what is essentially a V-block frame, with the front sight on the barrel and rear on the slide. A burr on the frame in front of the attachment point would effectively tip the barrel up, which should raise POI; but it also raises the front sight, which would tend to compensate. The reverse for a burr which tipped the barrel down, behind the attachment screw. What seems obvious...bent barrel causes group movement...on closer examination becomes much more complex. I'd remove any burrs, on principle, but I'd also be prepared to replace the front sight with a higher blade. On a used gun, it's a good bet that someone tried to 'adjust' a high-grouping gun by filing down the front sight, which of course is just the opposite of what should be done. slabsides