Oehler Model 35P Chronograph John Barsness
After long use, John found his Chrony was most accurate under cloudy skies, without the diffuser screens.
exactly how fast bullets left their rifl es. Chronographs were very expensive, and normally owned only by ammuni- tion manufacturers and the military. Shooters were forced to take the word of companies such as Winchester, Du- Pont, and Speer about muzzle velocity. Today’s varmint hunters would feel semi-crippled by this handicap, because we depend so much on sophisticated ballistic programs to predict where our bullets will land far across prairie dog pastures and coyote coulees. Eventually, however, affordable
Believe it or not, once upon a time varmint hunters didn’t know
chronographs became available to home handloaders. I bought my fi rst chronograph in 1979 from a small Washington state fi rm called the Custom Chronograph Company. The price was $160, around $500 in 2011 money, and included a set of light screens, which were pretty new technology back then. The unit was rather cumbersome,
since the screens had to be mounted on a 2x4 and the 2x4 mounted on a tripod. Long wires from the screens plugged into the main unit, a small aluminum box that sat on the shooting bench. Like
Page 188 July — September 2011
With a little practice, the Oehler 35P sets up quickly. The three screens provide a “proof channel.”
many chronographs made back then, the Custom Chronograph didn’t provide an instant readout of the velocity on a screen. Instead, the shooter turned a rotary switch after each shot, which lit up a series of red lights next to a set of numbers. The sequence of these num- bers was then looked up in a booklet listing the actual velocities. Today this may seem incredibly
slow and laborious, but back then much of life was slow and laborious. Humans typed on typewriters and sent paper letters via snail-mail. Phones weren’t portable, and didn’t take messages. In comparison, the Custom Chronograph seemed incredibly high-tech. My first chronograph revealed
many truths, among them that hand- loaders are optimists. I fi rst discovered this about me, during my fi rst chrono- graphing session with three rifl es. One was a .22 rimfi re Marlin, used to make sure the chronograph was working properly before sending any expensive centerfi re handloads downrange. Ev- erything functioned nicely, indicating a velocity of just under the listed 1,200 fps of the Remington ammo. Next I chronographed the deer
handload for my .243 Winchester, the 105-grain Speer spitzer and 41.5 grains IMR 4350, the maximum load listed in the Speer manual. Since I’d duplicated the load precisely, right down to the CCI primer, and Speer also used a Remington 700 with a 22" barrel for testing, I’d al- ways assumed that the velocity was very close to the 2,995 fps listed in the manual. Instead, the chronograph showed
a velocity of less than 2,800 fps. How could this be? I’d taken a dozen deer and pronghorns with the load, at ranges out to 250 yards, and the bullets hadn’t bounced off. Well, that certainly wouldn’t be
the case with the third rifle, another Remington 700 chambered for the .270 Winchester. Its favorite (and very ac- curate) load was the 150-grain Hornady Spire Point and 58.5 grains of the old military-surplus Hodgdon H4831. A year or so before buying the
chronograph, I’d carefully sighted-in this rifl e 3" high at 100 yards, then shot it again at a measured 300 yards. The last four shots in my box of handloads made a 1¼ " group (I told you this was an accurate load), with the center only 2" below the point of aim. I compared this
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