oneatatime's statement prompted me to start this thread.
Since I do not plan to shoot much, if any, over 300 yards, my questions will be based on this.
First, a few local shooters say I am wrong testing for groups at 100 yards. 200 at least, if not 300. For over 50 years I have been under the impression that if I can get consistent 1 MOA with, say, my 22-250, accuracy at longer distances is a given within reason. As an old really long distance ground hog exterminator, I can attest for shots up to approximately 500 yards. 53 gr Sierra BTHP with 33 grs of 3031. 1" round bull staright Douglas barrel air gauged. Rem 700 action that I bedded in a Bishop benchrest stock. Years ago.

We can get into yaw and other stuff that can happen before a bullet goes to sleep but if it prints great groups, do we care?
I am aware of really screwing up a bullet's BC because of instability but under 300 yards do I care?
I guess I should get it right the first time in case I get bit with the 1000 yard sickness.
For those who shoot 600 yards or less, how do you get comfortable with your bullet groups?
PS: It is a single shot

I have the Lee 250 gr mold. And I have the lever gun. I have tried so many combos it is getting tiresome. Almost all my tests have been at 100 yards.
Expecting the C Sharps anyday and I am anxious to take it to the range. I am not giving up on the Marlin but more time will be devoted to the Ho Wall.
Which brings us back to the subject. I will begin testing the C Sharps at 100. Easier to see the target. Easier everything it seems. If I get 3" groups I will not try 200 yards. 
So why would anyone START at 200 yards or more when the load is not tested at 100 yards?

I always start at 200m, unless I'm sighting in a new rifle or scope/sights.  Even then I usually get on paper at 50 and then go directly to 200 for CF rifles.  I think you should develop your loads for the maximum distance that you intend to shoot at.  There is no point doing load development a 300 if you intend to do your shooting at 200 though.

As far as shooting to 600, sometimes you will find that your best load at 200 is not your best load at 600.

Chris.

In Bryan Litz's very interesting book on long range shooting he recommends testing at 100 yds. to minimize outside factors. It is particularly good for isolating mechanical things. Our lead bullets work in a much narrower range than high power jacketed bullets so there needs to be some load tuning going to 200 yds. somethings. I've never had a 200 yd load not shoot at 100.

I only shot one or two shots at 50yd to set the mechanical zero. Same at 100yd. Then enough to do some testing with 200yd loads at 200. Same at 300yd, 300m, 385m, 500m & 600yd. Much prefer to test at the distance the particular load will have to perform at. Takes some time at the longer distances, but have to figure out why it works at 300 and not at 600. I tend to have loads for each distance (which is a bit odd, as I really don't care for reloading). Be easier to shoot one load.

P1 wrote on Oct 12^th, 2017 at 4:32pm:

I think most of the comments recommend starting at a hundred yards or less. I believe the comments about starting further out or spending very little time at a hundred yards are because some of the folks have worked out the variables to their satisfaction, and a new bullet is now the only variable.

My expectations of accuracy depends on the rifle and my intended use. That is what makes shooting fun and sometimes expensive.
The first nice rifle I had built in the early 80's cost $600. It was a hunting rifle in 300 win mag on a Mauser action with a premium Douglas barrel and a Weatherby reject stock. It shot minute of angle out to 500 yards. I asked my smith about getting into high power competition and shooting out to 1000 and he explained it simply. Spend 3x more money on components and I might get twice the accuracy, 1/2 minute.
So I guess for most people it's not only how hard you hold but how much you spend. I know no matter how much I spend that  a few certain friends can beat me with my own rifle no matter the distance or particular rifle. Most any 22's will shoot tight at 50 feet off hand, just depends on whose hands. Same for a $3000 bench rifle at 200.
I prefer 200 yard load development for most centerfire rifles and 50 and 100 testing for rimfire. Wind conditions are always a consideration. On new equipment or new load I always try for dead wind zeros so I can see what effect the wind has later for a rifle and load that shows good potential for longer ranges. I like to carry a proven rifle along with a new to me load or rifle to help verify my own abilities for that day. Practicing at longer distances gives me more confidence and that is what your local shooters are probably striving for. Longer ranges exaggerate poor form more so than 100 yard shooting (IMHO).

SSShooter, that initial bad press gave the 243 the edge and the 6MM never recovered. Better round in my opinion. I had a Savage 110 action barreled with an 18" straight taper Douglas barrel and the twist was requested to stabilize the 100-1105 gr bullet. It was built for my youngest son; however he adopted my Weatherby Vanguard in 7MM Mag.
That 6MM wil do MOA to 300 yards. Still have it.


100 yards.
Some of you are aware that I have spent months and months trying to get close to MOA out of a Marlin 336 38-55. First owner, apparently and unfortunately had it throated. In my reloading shop I have all the powders that are associated with the 38-55 except 4759. The bore slugged .379. I have tried .77 to .380. In 50+ years of shooting I have all the popular primers. I have neck expanders, and RCBS 38-55 dies. Not Lee. I have bullets that are 20 Brinell and down to 8 Brinell, 240 to 265 grains. Crimped, not crimped sized, not sized, neck sized. Loaded them long and in between. 
Tempted to construct a breech seater. 
Trying to get the Marlin to group consistently under 2"s is enough of a chore much less exacerbate the task. 
But then, if I have ever had the "chore" of shooting a rifle for group, I always start at 100 yards (or less).
The 1000 yard bolt action group realizes that their bullets (some) will pass through paper with a yaw, then go to sleep far out there. However that group at the paper will not be embarrassing.
Seems the choice of 100 yards or going to 200 yards or longer may be a personal preference (hang up) that has evolved from exposure or mentoring.