WEATHERBY CARTRIDGE DESIGN

I have gotten the drift, from comments you have made, that you believe Weatherby cartridges are of superior design than many others. Please explain.

Robert S., California


Whether Roy Weatherby was an accidental genius, or had an instinctive idea of what his cartridge developments would produce, is left in part to speculation. However, his earlier writings, from the 1940s and 1950s, seem to indicate that he did have an understanding of fluid (and therefore, gaseous) mechanics and dynamics. Thus, the gorgeous double-radius shoulder design. I, for one, believe that a shoulder design can lead to changes in combustion characteristics that are either more or less favorable to accuracy. Let's look at an example:

One of my favorite cartridges is the 7mm Weatherby Magnum. Having chambered it in match-quality rifles essentially identical to rifles chambered for the copycat 7mm Remington Magnum, the Weatherby produces more velocity and superior long-range accuracy. Why? The cases are of the same capacity, so how is that possible? It's the difference in the shoulder design. The Weatherby produces beautifully smooth combustion that continues as the bullet is accelerating down the barrel, while the Remington develops what I call "shattered" combustion. If you're a car guy, as so many enthusiasts of fine rifles are, then you know the advantage that headers provide in removing pressurized exhaust gasses, versus the restriction of a conventional factory exhaust manifold. With the conventional manifold, exhaust bunches up and then is released many times each second, which can be seen and recorded only with special photography and instrumentation. In recent years, with auto manufacturers having such equipment, exhaust manifolds have been improved. Power and gas milage has improved along with the manifold improvements. Because of the superior design of the Weatherby shoulder, the 7mm Weatherby Magnum case can be filled with more powder than the Remington; the improved load density being the physical reason for the increased velocity. In fact, the 7mm Weatherby Magnum produces about the same velocity performance as the considerably larger 7mm STW, but, in my experience, cannot match the 7mm Weatherby for accuracy.

The Weatherby bashers have lined up to expound their discontent for decades. I've been shooting centerfire rifles since 1953, and have no political or financial connection with any manufacturer. Roy Weatherby was at least a remarkable innovator, if not a natural ballistic genius, and I really like his cartridge designs. Today, there is a new phase of somewhat "softer" bashing. The comment "unnecessary belt" is being tossed around by some who prefer beltless magnum cartridges. Whatever. What is lacking here is their maturity to simply prefer one thing over another and not criticize the other. There are a whole mess of us still breathing and shooting that remember the reasons for the belt, who understand that it really doesn't hurt a darn thing, and that a lot of cartridge development would have passed us by without it. In the past year, I had enough from one such individual. We headed to the range for a grudge match; he with his very pricy 300 WSM custom everything, and me with a 1990s production H-S Precision-built Winchester Model 70 Sharpshooter in 300 H&H Magnum. The individual, my friend, now clearly understands that short, fat, beltless cases with relatively sharp-angled necks are not necessary for winning.

JDC

Do your comments about the 7mm Weatherby Magnum versus the 7mm Remington Magnum mean that you do not like the 7mm Remington Magnum?
Johnny R., Montana



Absolutely not. Both are excellent cartridges. However, as stated, I regard the 7mm Weatherby design to have some advantages. At this time, I have four sporting rifles chambered for the 7mm Remington Magnum, and one with a heavy barrel that I consider to be more for specialized hunting of various game in open country than for informal target use. Incidentally, three of the sporting rifles have genuine walnut stocks, which are sadly disappearing from our modern (and less sophisticated) culture. Two of the three have very fancy wood; one is American walnut, the other is Turkish.

JDC

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