with the trajectory tables in the Hornady manual, which indicated that my load was going just about 3,000 fps — very fast but not impossible for a 150-grain .270 bullet. So with extreme confi dence I put a
Spire Point over the light screens, then fl ipped the switch through the red lights. A look at the booklet gave a velocity of right around 2,800 fps. A second shot had almost exactly the same result, and so did a third. What?! The reason for my erroneous ve-
locity calculation, of course, was that the Hornady trajectory tables were for bullets fi red at sea level, and the range outside Missoula was around 3,500 feet above sea level. Bullets fl y a lot fl atter in the Rockies than they do along an ocean beach. The Custom Chronograph began
accompanying me to every range ses- sion, and other shooters were often very interested. Occasionally one of these guys would get up the nerve to ask if he could maybe put a round or two over the light screens. Of course, I’d say sure, and just about every time the results would make the shooter a little angry. Why? Like me, they always be-
lieved they were getting the highest pos- sible velocity out of their handloads, and the infernal machine almost always said the velocity was at least 100 fps slower, and sometimes 200-300 fps. In fact, some of the boys refused to believe the chrono- graph, somewhat understandable since it didn’t provide a direct readout. Over the years, however, the Cus-
tom Chronograph proved its accuracy over and over again. It was a very reli- able unit, almost never “missing” a shot, and giving consistent readings in widely varying light. Sometime in the 1990s it quit
working. I called the “company,” which turned out to be a handy rancher who made chronographs on the side. He’d quit making them a few years before, put out of business by much cheaper and handier chronographs. He could fi x my unit, but the fi x would cost more than one of the new Shooting Chronys. So I bought a Chrony. The Chrony showed very close to
the same velocities with various rifl es and loads as the Custom Chronograph, though it tended to “miss” a shot now and then. It was a lot quicker to set up, since it consisted of a single unit
This the author’s setup for fi ring test loads over a chronograph.
mounted on a tripod, with an LED screen that immediately showed the actual velocity. It lasted for several years until one day a bullet from a .41 Magnum revolver centered the LED screen, caus- ing both Chrony and tripod do a double back-fl ip. (As a shooting-addict friend once suggested, “If you haven’t shot a chronograph, you haven’t shot much!”) I immediately bought another
Chrony, as by then a chronograph had become essential to my professional life
as a gun writer. This Chrony proved a little temperamental — or perhaps I was becoming more demanding. Along with missing shots (at about the same rate as the old one) it had a tendency to give different readings under different light conditions. This was especially noticeable
during a partly cloudy day, when the light sometimes changed from sunny to cloudy during a fi ve-shot string. The readings were about 5 percent slower
The Oehler 35P shows the velocity in three places: an LED screen, and twice on a printer. The second printed velocity is the proof channel’s reading.
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