Boyd, I have pondered just that question. If you move to 1,000 yard benchrest, where the absence of stock rules make a design to achieve a "center of mass" build easier, there have been several rifles built that approached this. The one that came closest, by his design and work, was Joel Pendergraft's world record holding heavy gun (his record has since been broken).
Now one 10-shot group, even if it is a record, proves very little. But the rifle was used, in two configurations, with two barrels, for over 4 years. In its first incarnation, Joel won more heavy gun matches at Hawks Ridge than any other single competitor. The rifle was rebuilt, with a different tube and barrel, and that one set the world record.
Before Joel, there was Charles Bailey's heavy gun -- actually, again, two different builds, and at least three barrels. What was so often remarked about with this rifle was the tensioned barrel. Less remarked was the mass of the two rifles, admittedly in large part due to the tensioned barrel setup, was centered around the centerline of the bore.
Then there is mine, again, two builds. I chose a design somewhat simpler to execute, so I do not have a perfect distribution of the mass. But it is close. Again, more than one barrel. I've not had the success of Joel and Charles Bailey, but the rifle is a consistent performer -- it's performance seemingly in direct proportion to how good the barrel is.
These rifles do not exhibit vertical, save due to conditions. This from reasonably extensive testing at 100 yards, where you have a fighting chance to get a handle on conditions. Neither Joel nor I had single digit ES for velocity. As I remember, SD did approach the single digit level. Whether or not that is a requirement I don't know. Current theory predicts that optimizing time-in-bore compensates for velocity variations, but only if the barrel has a cyclic vertical movement. Without that movement, you should get vertical dispersion, right? But we don't.
* * *
I've also felt, for the point-blank game, that one reason aggs have come down is that stocks have gotten lighter and scopes heavier. It use to be you had a 32-ounce stock and a 15-ounce scope. Now each is closer to 20 ounces. Maybe it's all just bullets and barrels, but the changed distribution of mass in a typical LV rifle is there.
The reason I brought up the "longitudinal" distribution of mass is that it would be reasonably easy to build a short-range HV rifle with the mass radially centered -- or top/bottom, left-right, if "radially" is the wrong term. Complete centering in all planes would not be possible given the rules, that would have to be an unlimited.
I don't know of any PB unlimiteds designed to center the mass around the bore. I have the pieces. If I ever get it built, I'll have one. My first one was tension-barreled, but a pendulum style, with several design flaws.
Truth to tell, I'm building much less these days, and shooting much less. I don't know if I'll ever get either the HV or unlimited built. And even if I do, they will still be only one data point. Still, they would show whether or not there was vertical with that "untunable" design.
Now one 10-shot group, even if it is a record, proves very little. But the rifle was used, in two configurations, with two barrels, for over 4 years. In its first incarnation, Joel won more heavy gun matches at Hawks Ridge than any other single competitor. The rifle was rebuilt, with a different tube and barrel, and that one set the world record.
Before Joel, there was Charles Bailey's heavy gun -- actually, again, two different builds, and at least three barrels. What was so often remarked about with this rifle was the tensioned barrel. Less remarked was the mass of the two rifles, admittedly in large part due to the tensioned barrel setup, was centered around the centerline of the bore.
Then there is mine, again, two builds. I chose a design somewhat simpler to execute, so I do not have a perfect distribution of the mass. But it is close. Again, more than one barrel. I've not had the success of Joel and Charles Bailey, but the rifle is a consistent performer -- it's performance seemingly in direct proportion to how good the barrel is.
These rifles do not exhibit vertical, save due to conditions. This from reasonably extensive testing at 100 yards, where you have a fighting chance to get a handle on conditions. Neither Joel nor I had single digit ES for velocity. As I remember, SD did approach the single digit level. Whether or not that is a requirement I don't know. Current theory predicts that optimizing time-in-bore compensates for velocity variations, but only if the barrel has a cyclic vertical movement. Without that movement, you should get vertical dispersion, right? But we don't.
* * *
I've also felt, for the point-blank game, that one reason aggs have come down is that stocks have gotten lighter and scopes heavier. It use to be you had a 32-ounce stock and a 15-ounce scope. Now each is closer to 20 ounces. Maybe it's all just bullets and barrels, but the changed distribution of mass in a typical LV rifle is there.
The reason I brought up the "longitudinal" distribution of mass is that it would be reasonably easy to build a short-range HV rifle with the mass radially centered -- or top/bottom, left-right, if "radially" is the wrong term. Complete centering in all planes would not be possible given the rules, that would have to be an unlimited.
I don't know of any PB unlimiteds designed to center the mass around the bore. I have the pieces. If I ever get it built, I'll have one. My first one was tension-barreled, but a pendulum style, with several design flaws.
Truth to tell, I'm building much less these days, and shooting much less. I don't know if I'll ever get either the HV or unlimited built. And even if I do, they will still be only one data point. Still, they would show whether or not there was vertical with that "untunable" design.