From the Houston Warehouse chronicle:
Friends, we're talking about firing group after group approximately the same size as the gap on your spark plugs. This, with the barrel cleaned between every six shots — one group plus one fouler. But didn't he get an occasional larger group? Something really horrible, something maybe in the (shudder) teens? "Not unless you did something wrong," Virgil responded indignantly, flinching at the implication of his rifle sinking to that dismal level.
How could the rifle and the man behind it be that consistently accurate? Virgil told me in great detail. "First, you shoot free-recoil. After a while, after all the thousands of rounds I fired in the warehouse, I developed a technique that was practically infallible. I did exactly the same thing every shot. I was like a machine, and once you find out what works, you don't change anything. We discovered that if you want a gun to really shoot, you can't cheek it, you can't shoulder it, you can't hand it, you can't thumb it. The only thing you touch is the trigger, and I tried to put my fingerprint on the trigger exactly where my last fingerprint was. I didn't even touch the bench. I planted my feet solidly on the floor and kept them right there.
"Your shoulder should be 3/16" to 5/16" from the stock so you can catch the rifle immediately when it recoils back," Virgil advised. "Otherwise the rifle will get back too far and disturb the rear bag."
The rear bag and the way you manage it is crucial, Virgil explained. First, he positioned the rifle on the bench so the stock barely protruded from the
"V" of a rabbit-ear bag, then he pounded the stock firmly into the bag. As already mentioned, when the rifle recoils, it's important that the bag stay put. With proper bag technique, when the rifle is returned to its firing position, any sight corrections should be slight and made by tiny manipulation of the rear bag. The less bag adjustment, the better. Consistency is everything.
Virgil packed his rear bag very firm with casting sand, which is about 33% heavier than common sand. He then applied water and formed the "V" to the rifle stock by pounding the stock into the bag and allowing the leather to dry. Done only once, this step hardens the leather and makes the stock slide smoother. A mixture of equal amounts of talcum powder and white graphite applied to the back and front bags provided smooth sliding of the rifle, even in very humid conditions.
He packed the front bag as hard as iron. Here he employed a one-to-three mixture of Portland cement and casting sand. The cement doesn't set, but it does help hold the bag shape by resisting the twisting force imparted to the fore-end by bullet torque.
Virgil fired his many zero-level groups without any side support for the front bag, but he strongly advocates the pedestal fore-end stop. He adjusted the stop so the front bag supported the fore-end about halfway from the end of the fore-end to the receiver. He said if the bag is positioned farther forward, this part of the stock is too springy, and accuracy will suffer.
When Virgil returned his rifle after firing, he bumped the fore-end stop and then pulled the rifle back "one-millionth of an inch". In the warehouse, he found that contact between the stop and stock tended to deteriorate accuracy.