Now here's the rest of the story. . . . . .
Those service rifles are as accurate a record setting benchrest rifles used at 1000 yards. Able to keep all fired shots inside 7 inches at 1000 when properly tested.
Here's some reasons why they sometimes shoot inside 20 inches at 1000 off the shoulder:
* First, the best prone competitors (smallbore, high power, etc) can hold about 6 or 7 inches on paper slung up in prone when the wind's calm. Their aiming point bounces up and down with some sideways movement 'cause their heart's pumping blood into their muscles. They try to get their shots off inside a 5 inch circle at 36,000 inches; 1/2 MOA; most will be called as such but the others are sometimes at the far edge of that aiming area.
* Second, nobody shoulders a rifle with the same exacdt pressure against their body with arms holding it the same way for every shot. The tiny variables cause the rifle's recoil while the bullet's going down the barrel to move the bore axis off the point of aim a bit different for each shot when the primer detonated. Folks who are the most repeatable doing this typically shoot the best scores. But this causes an extra 1/4 to 1/2 MOA increase in the group size they can shoot.
* Third, most of their wide shots are horizontal ones. It's difficult to estimate windage corrections for a change in cross wind; with faster winds it's harder. And if an exact correction is made but the wind speed changes after the bullet's left and before it goes theough the paper, it's gonna be a wide shot. Good shooters try to keep impact a bit into the wind as gusts cause more problems that let ups; their errors have more 10-ring spacefor the bullet to fall in. A half mph of cross wind gust blows those bullets up to about 5 inches at 1000 yards.
* Fourth, getting a service rifle's post front sight alignment perfect with the rear sight's hard to do, they're not going to end up pointing the barrel exactly perfectly for each shot like scope's do. That adds another 1/8 to 1/4 MOA to the group fired.
So anytime someone shooting prone putting all their shots inside 20 inches and half of them in 10 inches, they usually sit on top of the mountain of scores fired. The national record with sevice rifle in a 1000 yard individual match is, I think, 200-14X.
