I read on the internet about the 1" 5 shot group at 100 yards throughout the 90s.
I went to all kinds of ranges, and no one ever got one.
Then in 1999 I saw two guys do it.
One at Issaquah with a .223 Coyote Win M70.
One at Tacoma Sportsman in Puyallup with a Mosin Nagant.
Meanwhile everyone on the internet did it every day.
The internet is a lousy place to learn accuracy, but may be the only place.
Lousy, because of all the benchrest red herrings.
I have come up with schpeal to help guys not spend years like me.
1) Test rifles in 6 mph or less wind or test at 50 yards.
2) Use a 10X or more expensive scope or a 14X or more cheap scope.
3) Spend two hours and ruin several bronze brushes getting the Copper out. The brush does no good if the bristles measure less than the groove diameter. Brushes can wear out in 10 strokes and become hand me downs to smaller calibers. You may only get 10 shots before you are Copper fouled again, and the first shot is a fouling shot. So have the rifle sighted in when you clean it. Look into the muzzle at a 45 degree angle, and rotate the rifle. You should be able to see the last 1/4" of lands and grooves. The Copper may appear a Gold color or a red color. You must scrub until all Copper is gone.
4) Most rifles get the best group at 50y or 100y with a reduced load with faster powder and light weight Vmax bullets seated long.
5) Don't use an expander ball. If a piece of brass has been resized and used an expander ball in the same step, it is now bent. The best way to get the neck straight again is to fire the brass again. We don't like bent necks because that makes the rear end of the bullet not concentric with the bore.
6) Seat the bullet long. Half way between touching the lands and getting stuck in the lands. If the front end of the bullet is jammed into the lands, at least ONE end of the bullet is concentric with the bore.
7) Practice dry firing on the bench until the cross hairs stay on the bullseye. Adjust bags, benchrest, posture, or whatever it takes.
8) Float the barrel. Use a dollar bill to check that the barrel does not touch the stock from the end of the stock all the way back to within and inch of the receiver. Anything touches the barrel, sand, chisel, drill, or file it out of there.
9) Make sure the scope mounts [or bases as Brownells calls them] are tight to the receiver. Those screws commonly get loose. The ring screws never get loose. But very often bad groups are caused by loose scope mount screws.
10) Make sure the action screws are tight. Hold the rifle with one hand on the rifle wrist and with the other palm, punch the barrel. The barrel and stock vibrating like a tuning fork sound should be a bongggggg. Not a buzzz. Not a bump. The under damped exponential decay of a sinusoid indicates a stiff connection. We need it stiff to make the stock count as part of and a consistent part of the recoil reaction before bullet escapement.
Let me try again, in more of a comic book version:
Big effect on accuracy
1) shoot when there is no wind
2) get a high power scope
3) practice dry firing and keeping cross hairs on bullseye
4) clean out Copper fouling in bore
5) good bullets
6) No expander ball use
7) jam bullet into lands
8) heavy gun and light bullet
9) float the barrel
10) keep barrel cool
11) expensive bull barrels
12) make sure scope mounts are tight to receiver
Little or no effect on accuracy
1) True the action face
2) true the inner C ring
3) lap the lugs
4) true the bolt face
5) chase the threads
6) speed up the lock time
7) glass bed the action
8) pillar bed the action
9) get a 1 ounce trigger
10) turn the case necks
11) weigh the brass
12) de burr the flash holes
13) weigh each powder charge
14) try different powders
15) use benchrest primers
16) lap the scope rings.
17) Dial in bore when chambering
18) re crown the muzzle