I shot a water buffalo at maybe 30 yards with a 175-grain Barnes Super Solid, a perfect brain shot. No problem. Hunting with hounds, I shot a capybara at about 10 yards, and I killed a monstrous wild pig at maybe 10 feet. No problem.

I also missed a collared peccary running across a narrow opening, a fast shot at 50 yards. A tough running shot that looked good but wasn't. No problem. But since we were also going to hunt free-range blackbuck antelope I thought I'd better check my zero. I fired a shot at a 50-yard target and discovered it now was a bit low, so I adjusted the scope.

The next morning I missed another shot at a collared peccary, almost the same situation--moving fast across a narrow opening. Had I connected it would have been a fantastic shot, no shame in missing, nothing lost in trying--except the crosshairs had looked really good when the rifle went off.

I headed to the range and hung a target at 100 yards. The rifle was now left, right, up and down and was holding an eight-inch group.

The screws were all tight, humidity hadn't changed, but a very good scope, never mind which brand, has suddenly and mysteriously gone south. I don't much care about missing a javelina, but if I hadn't gotten suspicious I wouldn't have had a snowball's chance of taking what turned out to be a great blackbuck antelope with a borrowed .270.

These things shouldn't happen, but they can and they do. There is no way to properly guard against them, simply because any mechanical device can fail. However, what you can do is follow your instincts.

If you have even the slightest suspicion of a problem, chase it down and try to isolate it. Most of the time the problem will be the shooter, whether it's you or me--but not always--and when a scope goes out you have no choice but to switch it out or borrow a rifle.