Lengthened Forcing Cones
One of the most highly touted features of a shotgun today is the mysterious lengthened forcing cone. Lengthened forcing cones have been touted to reduce recoil, give higher velocities, improve patterns and just about everything else you can imagineóperhaps giving us more miles per gallon as well. It falls into the category of what we like to call a "feature."
Features donít have to do much; in fact they donít have to really do anything at all. For a feature to be a ďfeature,Ē it just has to exist. If it exists, it can be advertised. It helps if we canít measure the benefit of this feature easily, or at all. That way, no one can say we are wrong.
Shotgun makers like features. If they crow about it long enough and loud enough, then sooner or later they donít even have to pretend to know what it does, or state what it does. When they advertise it in big, bold letters, people assume it is a very good thing, otherwise they wouldnít make such a fuss about it.
That brings us to "Lengthened Forcing Cones!" or perhaps the more esoteric, "Precision-crafted, Highly Polished, Elongated Forcing Cone." They are about the same thing, of course, but we can ask a little bit more for our features if they take longer to say, or are harder to pronounce. "Cryogenic Elongated Forcing Cones" likely sell for a bit more.
When was the last time you saw a good shotgun pattern and rushed to measure your forcing cone? After someone shoots a good round of sporting clays, do people gather round and plead in hushed tones, "Could you tell me the length of your forcing cone, please?" What is the preferred forcing cone length of Olympic medalists, anyway? Somehow, that little bit of information never seems to make the news.
A forcing cone, of course, is the transition area from chamber dimension to the bore of your shotgun. The length is not really the point; it is the degree of taper. In theory, a more gentle taper is less disruptive to shot and wad. A short cone might be a bit under a half-inch section with a correspondingly sharp taper, where a long cone might be two or three inches or even longer. The beauty of a lengthened forcing cone is that we donít have to say what the length was before you lengthened it, or what it is now. This is particularly amusing in the case of brand new models, never before manufactured, with "lengthened" forcing cones. It forces the consumer to believe that they were going to make it with shorter cones, but erased that part from the production prints and then lengthened them. Even though they arenít any longer or shorter than they ever were, they only come one way, they are now lengthened because they could have made them shorter if they wanted. It is a lot like "room temperature," as no matter how hot or cold a room gets, it is still "room temperature."
Recently, I had a long session with one of top engineers in the industry, whose company has recently introduced a lengthened forcing cone on a couple of new models. After exchanging the usual pleasantries, the subject of forcing cones was breached. "You did some extensive R & D with these models, correct? A large quantity of shooting, carefully documented, with a variety of shells?" After being assured that this was indeed the case, with a great deal of time and money spent, I was told the new forcing cones gave beautiful and better patterns.
Naturally, I asked, "What can you show?" In other words, after all this R & D work, with a clean slate and the ability to use any forcing cone length you please, what is the documented benefit? A more even pattern? A higher percentage pattern? A 5% higher percentage pattern? 2%? 1%?
The answer was, "Well, no. We couldnít quantify any of that." I was a bit surprised. Nothing? No trend? Something perhaps with steel or other chaotic shot? Nothing with higher velocity loads, or higher payload loads? Nothing, not even an average of three pellets per shot increase in a 30 inch circle at 40 yards?
The answer was clear: "No, we couldnít find anything. The physics are sound, though, and it should work. We can say it doesnít hurt anything."
That is the crux of this biscuit. There are several approaches that sound good, or can at least be made to sound very good regardless of manufacturer or brand. In terms of tangible, real-world performance there is often nothing that can be reliably shown, or shown at all. In the case of elongated forcing cones, on the list of really important shotgun features of the day, it ranks very close to the search for Bigfoot. While we canít say that searching for Bigfoot will improve your shotgun patterns, we can confidently say that it doesnít hurt anything.
Copyright 2009 by Randy Wakeman. All rights reserved.