My thinking is that the center-of-mass = center-of-bore rifle is not what matters. My big tube guns, if you remember, have a piece of 0.75 inch thick, 13-inch long piece of aluminum functioning as a butt. Don't remember what it weighs; at the back, it is 5 inches deep, then to the bottom of that is bolted the 3-inch wide plate plate with steel guide rails to fit the rear rest (a short-range front sandbag). The weight is not insignificant.
This handles the torque, letting me use "only" a seven-inch wide front plate. Both Joel and CB had to go to a dual-post front rest.
My first tensioned-barrel rifle use a small 2-inch tube, and the stock was one of those 20-pound McMillan 50-caliber stocks, all below the bore line. Both Jeff Rogers and Tony Z's (Australia) rifles are the same (homemade stock), as was Dave Tooley's *compression* fitted barrel -- that was a Light Gun, as I remember.
So now we have compression and tension; to complete the picture remember Phil Jusilus' HG, which used a big tube, but neither tension nor compression, he simply used a spider-type bolt system to hold the muzzle in place.
All of these shoot the characteristic round groups. The load can be tuned, but the shape of the group stays the same. It just gets a bit bigger or smaller
That's why I think the double-cantilevered beam is the correct model.
You could argue that Joel's rifle shot better, and that was certainly true of the first barrel. But his second barrel wasn't so good, my tube gun stayed right with it. And Jeff Rogers "not-COM" guns hold a lot of Australian records.
Ideally, both the butt & muzzle would be cemented into a brick wall. But getting that to the line would be hard, never mind bench rotation...
